Um incêndio leva a vida de um dos membros da equipe 51 de bombeiros de Chicago. Após a tragédia, o tenente Matthew Casey e o tenente Kelly Severide apontam um para o outro como culpados pelo acontecimento. Além disso, Casey precisa lidar com o drama pessoal trazido por sua separação de Hallie, sua esposa.

Severide segue consumido pela culpa pela morte de Andy Darden. Para piorar ainda mais a situação, ele descobre que a viúva também o culpa pelo que aconteceu. Mais tarde, a equipe precisa resgatar dois adolescentes que ficaram presos nos destroços de um carro.

Casey sofre pressão para encobrir as causas de um acidente causado pelo filho de um policial, fato que culminou na paralisia de um adolescente. Enquanto isso, Severide ignora os avisos do médico a respeito da contusão em seu pescoço, algo que pode piorar caso ele não faça um tratamento apropriado. Para completar, Mills precisa tomar uma decisão.

Boden se torna alvo da imprensa após ser acusado de deixar um sem-teto morrer em um depósito. Enquanto isso, Severide ajuda uma senhora idosa. Já o detetive Voight continua a intimidar Casey. Para completar, Shay se reencontra com uma ex-namorada, ao mesmo tempo em que Hermann fica bravo durante um resgate no Dia das Bruxas.

Casey bate de frente com Voight, portanto, precisa lidar com as consequências. Ao mesmo tempo, o comportamento de Dawson no trabalho resulta em uma ação disciplinar. Já Severide vê seu braço falhar durante um resgate, então pede ajuda de uma representante farmacêutica, que também é uma ex-namorada.

Casey arrisca a própria vida durante um resgate, o que faz com que ele receba uma folga de Voight e sua pressão para mudar sua declaração. Enquanto isso, Dawson recebe ajuda de uma garota que salvou.

Severide atrasa os testes de drogas obrigatórios depois que ele e o resto da equipe são expostos a um laboratório de metanfetamina durante o feriado do Dia de Ação de Graças. Enquanto isso, Truck e Squad encontram problemas quando seguem para ajudar uma vítima ferida em uma disputa de gangues. Para completar, Casey realiza um parto no meio de um acidente de trânsito.

Peter começa a ter dúvidas sobre o seu futuro como bombeiro após se deparar com o corpo de uma jovem vítima de um acidente de trem. Em outros lugares, Dawson e Shay lidam com uma mãe abusiva; Severide salva uma vítima de ataque cardíaco, agravando sua própria lesão no processo; e Shay envia Clarice de volta ao seu ex-marido.

Jose Vargas é ferido em um incêndio e forçado a sair em licença. Chefe Boden dá conselhos a um adolescente suspeito de ser incendiário. Severige recebe um convite tentador de uma mulher que resgatou de um acidente de carro. Cruz tenta salvar seu irmão mais novo do envolvimento com gangues.

Several e os bombeiros são acusados de roubar um valioso colar de diamantes após responder a um incêndio na cozinha de uma residência de luxo. Enquanto isso, Cruz tenta salvar seu irmão de uma crescente guerra de gangues. Dawson convida Casey para uma festa de Natal. Shay fica frustrada com Severide.

Cruz é dominado pela culpa pela morte de Flaco, e procura a ajuda de Casey. Enquanto isso, Shay se recupera do trauma na cabeça, Severide para Dawson ajudá-lo a lidar com sua lesão, Casey tem problemas familiares e Herman tem dificuldades em aceitar um acordo de negócios.

Severide conta co Chefe Boden sobre sua lesão e faz algumas difíceis escolhas sobre seu futuro. Enquanto isso, Casey enfrenta problemas familiares e Dawson atende a um chamado e encontra apenas um sobrevivente – uma garotinha.

O Chefe Boden vai até a polícia após o adolescente incendiário Ernie iniciar um mortal incêndio. Enquanto isso, Severide procura seu pai após tomar uma decisão sobre seu futuro e Dawson e Shay encontram problemas quando atendem uma chamada.

Severide divide um passado com um tenente visitante. Dawson conta a Shay sobre seu segredo. Casey tem problemas familiares. Boden e sua equipe lidam com um lote ruim de heroína. Clarice e Shay são confrontadas com um novo problema.

Dawson se coloca em perigo após tentar ajudar Antonio em sua investigação. Em outros lugares, Casey e sua mão lutam com a sua nova relação, Severide visita alguém de seu passado e Hermann e Otis descobrem uma difícil verdade sobre seu silencioso companheiro.

Cruz sofre de estresse emocional, e acaba colocando a si mesma e a seus colegas em risco. Ao mesmo tempo, Casey, sua irmã e sua mãe tentam botar seus problemas para fora. Severide atinge alguém de seu passado, e alguns membros do esquadrão experimentam uma mudança de perspectiva após atenderem uma perigosa chamada.

O pai de Severide entra em confronto com o Chefe Boden sobre a morte de um antigo colega. Mills ajuda um motorista chateado após um acidente de carro. Chay toma uma decisão sobre o seu futuro com Clarice. Hermann investiga um mistério com a ajuda de Otis e Dawson.

Mills questiona Bennie sobre o incêndio que matou seu pai, e Casey, Severide e Bennie investigam dois misteriosos incêndios.

Uma tentativa de resgate em um edifício acaba em tragédia. Em outros lugares, os membros da equipe se desentendem com traficantes locais, o que pode ter consequências muito perigosas.

Apesar do apoio de Severide, Mills enfrenta o ressentimento de seus colegas. Enquanto isso, um candidato a paramédico trabalha alguns turnos com Dawson e Shay, Shay ajuda uma grávida que está sofrendo complicações enquanto seu marido está fora da cidade, Dawson e Casey se aproximam, e Casey recebe uma visita surpresa.

Severide é acusado de má conduta sexual, o que faz com que ele se depare com consequências potencialmente complicadas tanto no Departamento quanto no sistema legal. Ao mesmo tempo, o detetive Voight retorna para cobrar o favor feito a Dawson. Já Casey novamente mergulha em antigos padrões em sua vida pessoal.

Severide rebate as acusações feitas a ele, o que o deixa com problemas com Boden ao mesmo tempo em que ganha um aliado inesperado. Enquanto isso, Casey encontra felicidade em sua vida pessoal. Já Mills e Dawson enfrentam os desafios do relacionamento. Para completar, a equipe atende a uma chamada envolvendo a queda de um prédio.

Casey deve juntar-se a unidade de Inteligência, que agora é dirigida por Voight. Enquanto isso, Shay aguarda a paternidade, Mills e Dawson lidam com questões pessoais, e a casa apoia a grande inauguração de Molly.

A tensão aumenta quando a equipe atende uma chamada na penitenciária Cook County. Shay está esperançosa quanto à situação de seu bebê, enquanto Dawson e Mills encaram algumas decisões de relacionamento. Cindy finalmente entra e trabalho de parto do quinto filho de Hermann.

Evidências indicam que Severide é o alvo do incendiário. Enquanto isso, Boden bate de frente com McLeod, uma consultora de alta patente que está de olho no orçamento e no desempenho das unidades de bombeiros da cidade, em especial a 51 — que pode ser fechada. Já o tenente Casey reflete a respeito do aniversário de um ano da morte de Andy. Para completar, Shay suspeita da paternidade de Severide, enquanto Mouch recebe a visita de Mari, a namorada japonesa.

Casey têm problemas para lidar com suas novas responsabilidades. Enquanto isso, Severide teme o próximo ataque do incendiário, ao mesmo tempo em que Mouch comela a fazer campanha. Para completar, Dawson e Shay decidem que precisam sair mais.

Severide tenta provar suas suspeitas sobre a identidade do incendiário. Enquanto isso, Casey se acostuma com seu novo estilo de vida, ao mesmo tempo em que Dawson sai em um encontro com uma pessoa que frequenta o bar regularmente.

Severide está ansioso para capturar o incendiário, ao mesmo tempo em que Dawson e Shay ficam chocando com um chamado. Enquanto isso, as suspeitas continuam a apontar para Clarke como o informante dentro do departamento. Já Mouch faz campanha com a ajuda de Isabella, e Boden bate de frente com Gail McLeod.

O futuro de Boden na Firehouse 51 está por um fio e MdLeod fica relembrando-o de seus erros no passado, fazendo-o pensar em uma aposentadoria adiantada. Com Boden considerando suas opções, McLeod chama um convidado inesperado para potencialmente substituí-lo como Chefe. Enquanto isso, fica claro quem é o informante dentro do corpo de bombeiros e todos tomam medidas para deixar claro o desdém que sentem por ele.

Enquanto está praticando corrida, Severide passa perto de um local de construção selado e vazio com um garoto que ficou preso dentro de uma retroescavadeira que tombou, precisando de assistência urgente. Boden e McLeod continuam batendo de frente sobre o futuro do quartel do corpo de bombeiros e Boden fala sobre as novidades de seu futuro para Casey.

A equipe do corpo de bombeiros atende um acidente nos trilhos do trem. Enquanto Boden toma uma grande decisão a respeito de seu futuro, Severide descobre mais a respeito da mulher que viu ao lado de seu pai. Para completar, Shay e Dawson continuam a bater de frente.

Quando uma jovem garota é baleada nas redondezas, Cruz e Leon são forçados a pensar sobre a gangue que tentaram escapar. Enquanto isso, a batalha entre Boden e McLeod continua a crescer, ao mesmo tempo em que Isabella tenta convencer Mills a ir a um baile. Já o tentente Casey fica triste ao perceber que Dawson não está visitando muito. Para completar, Shay cansa do trabalho.

Boden tenta manter o corpo de bombeiros aberto. Enquanto isso, o romance entre Dawson e Casey cresce. Para completar, Cruz se preocupa com a segurança do irmão, ao mesmo tempo em que Severide e Katie tentam compensar o tempo perdido.

Tudo parece perdido para a brigada 51, que está prestes a fechar suas portas, mas Boden e o resto da equipe se recusam a esperar sentados pelo pior. Uma emergência ligada à estrutura de um apartamento testa os limites de todos e coloca o esquadrão em perigo. Enquanto isso, Dawson recebe uma notícia capaz de mudar sua vida e Greg Sullivam vai parar nas manchetes, o que terá um impacto imediato para Mouch.

Casey retorna para o trabalho após quase ter sido morto em um desabamento. Ao mesmo tempo, Shay conhece sua nova parceia, Allison, que é simpática com todos menos com ela. Já Dawson incia seu rigoroso treinamento na academia de bombeiros, enquanto Severise se prepara para ser instrutor. Enquanto isso, Clarke decide não falar com a polícia a respeito do assassinato do qual ele é suspeito.

Casey tenta convencer a si e a todos que está 100% recuperado do incidente que quase tirou sua vida. Enquanto isso, Shay continua a fugir do advohado que quer falar sobre o suicídio de Daryl. Já Otis e Katie se aproxima com jogos de tabuleiro, ao mesmo tempo em que Boden ajuda uma mulher com uma pessoa negligente. Para completar, Dawson percebe que uma colega da Academia está usando técnicas interssantes para passar nos testes.

Quando um motorista bêbado bate em um transformador, toda a vizinhança é deixada sem energia em um fria noite de Chicago. Dessa forma, cabe à brigada 51 ajudar os moradores. Enquanto isso, casey continua a mentir tanto para si quanto para Dawson sobre sua condição.

An emergency puts Dawson's firefighting skills to the ultimate test in this four-part digital series.

Severide deve deixar Lindsay e a unidade de inteligência a fim de encontrar Katie. Enquanto isso, Brent Seabrook e Duncan Keith, jogadores do Blackhawk, dão uma dica a Shay. Já Casey recebe mais informações sobre sua contusão na cabeça, enquanto Dawson trabalhar para passar no teste físico.

Severide está ficando impaciente com a polícia, já que Vince Keller está livre. Enquanto isso, o corpo de bombeiros faz de tudo para salvar uma garota presa dentro de uma lixeira de doações. Mais tarde, Mouch descobre que a secretária de Boden, Connie, não está para brincadeiras. Para completar, a equipe é chamada para conter um incêndio dentro de um prédio de 20 andares.

Severide fica no topo da lista quando a detetive Lindsay começa a chamar os suspeitos com motivos para fazer o responsável por Katie desaparecer. Enquanto isso, Jones ainda está tendo problemas para se encaixar no trabalho. Para completar, Hermann celebra 20 anos de casamento, mas ninguém apoia a ideia do presente que ele pretende dar à esposa.

Severide relembra seu próprio passado por um homem que salva de um acidente de carro, e fica determinado a ajudar a vítima. Enquanto isso, Casey e Boden estudam a situação de Jones. Ao mesmo tempo, Mouch e Dawson enfrentam problemas com o sexo oposto. para completar, uma ligação emocionante de trabalho se espalha pela Brigada 51.

Severide tenta ajudar Dave Bloom, um colega bombeiro de Denver. Enquanto isso, Dawson e Shay deixam a cidade para uma "noite das garotas". Já Jones sofre com o fato de que seu pai está pressionando Boden a respeito de sua carreira, ao mesmo tempo em que o perfil de Mouch na internet recebe um upgrade.

Uma nota de suicídio é entregue a uma surpresa Dawson ao mesmo tempo em que Severide mergulha ainda mais no passado obscuro de Bloom. Enquanto isso, Boden descobre informações chocantes. Para completar, Casey, com a ajuda de Shay, sai em busca de um item que vai mudar sua vida.

Casey e Dawson se voluntariam para ajudar o Chicago depois de uma explosão que instala o caos na cidade. Com um dos seus tendo desaparecido na explosão, a equipe de bombeiros é testada como nunca antes.

Com o apoio de todos, Dawson se prepara para refazer o teste para entrar para os bombeiros, porém uma chamada pode complicar os planos. Enquanto isso, Casey precisa discutir um assunto importante com Antonio. Já Severide dão boas-vindas a Rick Newhouse, a nova adição ao grupo. Para completar, Shay é surpreendida, enquanto Boden faz uma ação ousada.

Um incêndio em uma escola afeta Severide, que fica se perguntando se poderia ter feito mais pelas crianças. Enquanto isso, Dawson refaz o exame do corpo de bombeiros, enquanto Casey tenta algumas manobras políticas para ajudá-la. Para completar, Mills procura respostas sobre o passado de seu pai, enquanto os planos de Boden sofrem um atraso.

Boden obriga os membros da Brigada 51 a se recomporem após a explosão. Severide fica desaparecido por uma semana a mais do que o permitido e Casey tenta encontrá-lo. Enquanto isso, Newhouse leva notícias inesperadas a respeito de um dos parentes de Mills, enquanto Herrmann e Otis traçam novas metas com relação ao Molly's.

Severide retorna à Brigada 51, mas, claramente, não está no seu normal. Enquanto isso, Dawson conta as semanas até que comece como candidata no quartel de Austin. Já Mills descobre mais sobre a família de seu pai, ao mesmo tempo em que Hermann pede ao resto dos investidores do Molly’s para trazerem novas ideias a fim de melhorar os negócios.

Dedos são apontados e temperamentos explodem entre os membros da Brigada 51 e o Corpo de Bombeiros de Austin quando os caminhões colidem na rota para uma chamada. Enquanto isso, Boden planeja dar a Dawson a sua medalha, mas isso terá um custo. Já Mills confronta seu passado e futuro no mesmo dia em que a equipe do Molly's estreia o novo caminhão para servir refeições.

Dawson começa seu primeiro dia como cadete e tenta encontrar o equilíbrio com o tenente Casey dentro do batalhão. Enquanto isso, Mills deve pensar em um futuro que não inclui o esquadrão. Ao mesmo tempo, Severide confronta seus demônios de forma inesperada. Para completar, a equipe do Molly's se encontra com o inspetor da cidade para ter certeza de que o caminhão de comida está regulamentado.

Casey lida com as consequências do divórcio de sua irmã, Christie. Enquanto isso, Dawson e Mills se ajustam aos novos papéis dentro da Brigada 51. Ao mesmo tempo, Brett não decide se quer deixar Chicago.

Casey vai dar apoio a sua irmã Christie e enfrenta seu cunhado corrupto, ao mesmo tempo em que Brett faz de tudo por uma mãe que está precisando de ajuda. Enquanto isso, Mills conhece mais sobre o mundo da investigação privada, ao mesmo tempo em que Dawson inicia seu treinamento com Herrmann.

Os Membros da Brigada 51 lidam com o incêndio de uma casa e, quando o dono do lugar é resgatado carregando uma caixa suspeita, Severide traz Voight e Lindsay para investigar o caso. Enquanto isso, Mills se pergunta se os perigos do trabalho "por fora" de Newhouse vale o dinheiro recebido. Para completar, o Molly's II precisa de um bom chef de cozinha.

A grande explosão de um helicóptero em uma área populosa deixa uma trilha de destruição, o que leva os membros do corpo de bombeiros à ação, uma vez que vidas ainda estão em risco. O Esquadrão 3 se vê em uma situação precária, o que leva Brett a ser encurralado por um perigoso homem no meio da confusão. Para completar, Dawson fica chocada ao descobrir o que fez com que o helicóptero caísse.

O relacionamento de Casey e Dawson é colocado em teste quando o time responde a um acidente envolvendo o vazamento de ácido hidroclorídrico. Enquanto isso, Severide descobre mais sobre o passado de Brittany, enquanto Mouch enfrenta problemas na vida amorosa.

Uma casa em chamas leva os membros da equipe a correr contra o tempo para salvar o casal que vive ali dentro. Enquanto isso, Boden se prepara para começar uma nova família. Já a combinação de trabalho e família deixa Casey e Dawson separados. Para completar, o Molly II tem uma chance de brilhar no Chicago Holiday Fest.

A brigada recebe notícias perturbadoras, já que dois dos seus sumiram depois de uma chamada de rotina, o que leva os membros da polícia de Chicago a liderarem uma investigação. Enquanto isso, Casey e Dawson sofrem para equilibrar as vidas pessoais e profissionais. Já Boden e Donna lidam com a informação de que o recém-nascido pode enfrentar complicações, ao mesmo tempo em que recebem um surpreendente visitante de fora da cidade.

Severide e Dawson descobrem evidências surpreendentes em um depósito, que parecem estar conectadas ao incêndio que tirou a vida de Shay. Enquanto isso, a brigada se junta quando Chaplain Orlovsky se torna a vítima de um grave acidente de carro. Mais tarde, o pai de Boden chega para uma visita, mas logo começa a dar conselhos que não foram solicitados.

Mais pistas surgem a respeito do incêndio que tirou a vida de Shay, o que leva Severide a procurar uma inesperada fonte capaz de trazer informações pertinentes ao caso. Enquanto isso, a irmã de Shay, Megan, chega à cidade, fazendo com que os membros da Brigada relembrem a vida da amiga. Já Cruz se surpreende quando a avó de Otis se muda para o apartamento, ao mesmo tempo em que Boden encontra uma forma de ajudar seu pai moribundo a aproveitar suas últimas semanas.

Uma tempestade de neve chega e força a cidade a parar. Mills e Brett acabam abandonados à mercê do tempo enquanto buscam por um adolescente, ao mesmo tempo em que os membros da equipe servem de babá para um recém-nascido. Já Severide recebe uma oferta de emprego, ao mesmo tempo em que Boden bate de frente com o pai sobre o tratamento.

Boden se ausenta por razões pessoais e a equipe bate de frente com seu substituto temporário. Enquanto isso, Brett fica mais próximo de uma garota resgatada por ela, ao mesmo tempo em que as coisas se complicam quando Casey começa a namorar uma nova mulher.

O chefe interino comete um erro tático durante um incêndio em apartamento, fato que aumenta a tensão e coloca carreiras em risco. Enquanto isso, Mouch descobre que sua doação a uma clínica de fertilidade resultou em uma criança. Para completar, Dawson sai em um encontro duplo com Brett e Cruz.

Severide pede ao chefe Boden um favor para Scott Rice, um velho amigo que precisa uma segunda chance no departamento, mas Casey e Otis têm suas dúvidas sobre o assunto. Enquanto isso, Mills trabalha para recuperar seu status no esquadrão, enquanto Brett e Dawson decidem que precisam sair para uma noitada.

Durante um angustiante resgate em uma estrutura em fogo, Herrmann resgata uma criança presa, mas as circunstâncias questionáveis em torno do evento envia-lo em uma missão pessoal para localizar o pai e chegar ao fundo da situação. Severide tenta recuperar o tempo perdido, refazendo amizades de sua adolescência, enquanto Mills recebe notícias surpreendentes. Enquanto isso, o relacionamento de Cruz e Brett chega a um momento crucial, e Otis desenvolve alguns sentimentos inesperados.

Todos precisam trabalhar juntos quando a Brigada 51 atendem um chamado que envolve um vazamento químico mortal dentro de um prédio industrial. O esquadrão é testado como nunca antes e resgata os trabalhadores, mas muitos sofrem com problemas respiratórios trazidos pelo ocorrido. Isso faz com que o caminhão 81, o esquadrão 3 e a ambulância 61 transportem as vítimas para o hospital mais próximo, o Chicago Med. A situação passa de ruim para pior quando, em meio ao caos, um “paciente” realiza uma missão suicida — armado com uma granada — e diz que é o portador de uma doença mortal transmitida pelo ar. Tentando evitar que o homem solte o dispositivo explosivo, um membro do time fica severamente machucado e precisa enfrentar as contusões que ameaçam sua vida. Sem outra opção, o Chicago Med é forçado a entrar em quarentena até que os médicos e os especialistas determinem a severidade do vírus

O esquadrão é chamado para atender um acidentde de carro que leva Mills a, desesperadamente, trabalhar para salvar a vida do motorista que está ferido com seriedade. Enquanto isso, Casey tem dúvidas sobre Jack Nesbitt, cujo clube de strip ele está reformando nas horas vagas. Para completar, Hermann, Otis, Cruz e Orlovsky ajudam a deixar o time pronto para o campeonato de hóquei.

O incêndio de um apartamento ligado a um caso de estupro e tentativa de assassinato junta os membros da CPD com a Unidade de Vítimas Speciais, que conta com um caso similar sem resolução por mais de 10 anos. A sargento Benson chega de Nova York para dar assistência na investigação, algo muito familiar para ela. Para completar, dúvidas sobre um dos que fazem parte do esquadrão levam Severide a ditar uma lei, ao mesmo tempo em que Dawson coloca sua vida em risco durante um atendimento.

Casey concorda em trabalhar disfarçado para fornecer provas contra Jack Nesbitt. Enquanto isso, Otis e Severide continuam a discordar sobre a integridade de Scott Rice, o que causa tensão entre os membros do grupo. Já Hermann ajuda um amigo da brigada.

Casey coloca a vida em risco para descobrir os crimes de Jack Nesbitt. Enquanto isso, Boden precisa descobrir como criar unidade em uma casa dividida, ao mesmo tempo em que Severide questiona o próprio julgamento. Um incêndio sai do controle e ameaça as vidas dos membros da brigada 51, o que leva Boden e Cruz a arriscarem tudo para salvarem um dos seus. Para completar, Dawson recebe uma notícia capaz de mudar sua vida.

Casey is placed in a dangerous situation while working undercover to bring down a trafficking ring being run out of Nesbitt's club. The squad's high turnover rate results in an unwelcome surprise for Severide. Dawson recognizes that her life is about to change. A new candidate makes an unusual first impression. Residents band together to protest a drug den in their neighborhood.

Boden's job is on the line pending an internal investigation. Severide adjusts to Patterson, his new commanding officer. Dawson shakes things up at the work. Casey searches for important evidence in his investigation of Nesbitt. Herrmann tries to keep the peace with Molly's new neighbors.

Evidence that seems to exonerate Boden may not be enough. Brett and Chili find themselves in a precarious situation. The team responds to a stuck elevator in a hotel. Jimmy Borrelli's older brother wants him transferred to a different house.

The squad members come together to support one of their own. Herrmann tries to figure out how to reopen Molly's after it gets shut down. Severide digs deep into the arson investigation.

Boden offers to host a wedding at the firehouse after a fire destroys the original location, but it doesn't sit well with Chief Riddle, who also butts heads with Dawson over her ability to perform. Severide fights for his old position. Capt. Patterson finds himself torn between leadership and his colleagues.

Boden's new neighbor asks him for a favor that could have serious repercussions. Severide is upset when he's treated like a candidate by Patterson. Cruz is visited by a gangbanger who knows his brother. The team responds to a call that involves an 18-wheeler; and is thanked with tickets to see Rush.

Boden suspects his neighbor is setting him up; Severide, who's still on probation, receives a surprise visit from his father and also learns something about Patterson that could be a game changer. Romance blossoms at a fire department gala.

Boden believes Maddox is behind Serena's accusations. Severide reaches out to Jamie, who's Maddox's lawyer, in an attempt to help. Patterson questions whether Boden can remain chief. Brett and Chili suspect that a man passed out in a garden is connected to a previous call. Otis has problems with his social calendar.

Patterson fills in for Boden, who's trying to clear his name. Severide learns where Serena may be hiding. Herrmann and Otis give Freddie a job that keeps him close by. Jimmy and Chili draw more attention then either bargained for.

Herrmann fights for his life after being stabbed; Cruz hits the streets to find Freddie. Mouch proposes to Trudy.

The crossover continues on Chicago Med S01E05 Malignant (II) and Chicago P.D. S03E10 Now I'm God (III).

A tornado threatens Chicago. Chili makes a major mistake, which causes Brett to report her to Boden. Otis asks Dawson to help him solve his women troubles. Severide assists a Department of Homeland Security agent.

Freddie's father begs Herrmann to forgive his son's assault. Casey discovers that a makeshift shelter housing people displaced by the tornado may close. Casey attends a fund-raiser at the request of an alderman. Dawson and Brett experience repercussions after telling Boden about Chili's erratic behavior.

The team responds to a mass shooting; Casey investigates the missing money from the fund-raiser. Jimmy agrees to represent the firehouse in a boxing match against the Chicago PD's 21st District. Chili's behavior continues to be an issue for Brett.

Severide confronts Chili about her erratic behavior. Members of the firehouse rally around Casey, who they think would make a great candidate for alderman. Jimmy squares off against Antonio in the first annual "Battle of the Badges" boxing match.

The team responds to a suspicious call from a neighboring firehouse; and welcomes a new firefighter, though her addition has repercussions. Casey moves forward in his run for alderman.

Casey reconsiders his run for alderman after he's targeted by a propaganda campaign. The squad responds when a man is trapped inside of a burning car. Trudy's nerdy brother plans Mouch's bachelor party. Jimmy and Brett investigate a kidnapping on their own.

Severide and Cruz find a child's remains inside a chimney while investigating a possible carbon monoxide leak inside a home. In other events, Casey braces for the worst in his run for alderman while Alderman Becks continues to bad mouth him to the press.

Sylvie witnesses a murder and is threatened by the shooter not to go to the police. Firehouse 51 jumps into action when a fire breaks out at a restaurant and traps several people inside a vault. Mouch starts to get cold feet.

Casey steps up to help a teenager being bullied by a gang; Severide bonds with a detective’s son after her life is threatened; and Kidd and Herrmann go head-to-head in a test of bar knowledge.

Firehouse 51 unites to help a young boy in tragic circumstances. A high-powered political consultant helps Casey navigate a potential scandal. Cruz makes a mistake that nearly costs him his life.

Dawson saves a young boy from an apartment fire. Kidd's idea for Molly's doesn't go as hoped. Severide hits a wall while advocating for new fire masks. Cruz and Brett utilize a secret weapon to get Otis to see Dr. Halstead take a blood test.

The team responds to a building collapse that's trapped more than a dozen people. Dawson's quest to foster Louie is aided by a familiar face. Otis, who's on medical leave, meets his temporary replacement. Severide and Kidd continue to see each other. Casey is at odds with Antonio.

Boden and Jimmy are at odds. Kidd deals with her unstable ex. Dawson continues her quest to foster Louie. Casey's new political consultant urges him to think big. The team responds to a dangerous structure fire.

Severide and Stella search for Grant, who's AWOL from Chicago Med. Dawson questions her career path. Casey's relationship with his political consultant cools. Borrelli's anger at Boden over his brother's death boils over. Mouch and Brett partner on a new venture.

Casey and Dawson find themselves in the midst a potential political mess. Stella has to make a big decision about her ex-beau. The squad responds to an auto accident. Severide befriends a socialite. Brett and Mouch set aside their writing differences for the greater good.

Casey seeks help with a personal matter from Susan Weller. A rich party guy wants Severide to travel with him. Stella tries to help a sick street kid. Otis and Herrmann share their concerns about Molly's lack of customers.

Lt. Casey finds himself in a bad spot when a forklift accidentally pierces a tank storing acid. Casey is forced to use extreme measures to help a father and daughter in peril. Dawson and Brett respond to an elderly woman who has a difficult senior advocate. Mouch and Brett continue with their secret project. Otis shares some exciting news as he prepares himself for an unusual expedition.

Lt. Casey is unable to rescue a woman who becomes trapped inside her burning greystone, prompting him and Lt. Severide to butt heads over the husband's role in the tragedy. Herrmann is on a mission to catch a mystery tagger that keeps targeting their firehouse and Boden gets a surprise visitor. Meanwhile, Dawson and Brett respond to a 16-year-old boy who was injured during a romantic homecoming proposal.

While responding to a call in the field, Dawson accidentally hits a pedestrian who stepped in front of the ambulance, and is left to deal with the repercussions. Lt. Casey and Lt. Severide disagree and continue to investigate an arson case while Chief Boden is left to decide whether to attend an important function in New York. Elsewhere, in hopes of preparing him for a possible promotion, Lt. Casey puts Herrmann at the helm for a shift so he can discover firsthand what his superiors deal with.

It's a family reunion when Dawson and Antonio's mother and father come to Chicago for their big anniversary party, but things quickly turn south. When a deep secret comes to the surface involving his stepson James, Chief Boden decides to take matters into his own hands. Meanwhile, Casey tries to save a young boy during a harrowing call to a warehouse and Otis and Kidd become competitive at the mud-hundred race.

Lt. Casey and Dawson apply for permanent adoption of Louie, but quickly discover a hurdle. Firefighter-turned-medical student Jeff Clarke approaches Lt. Severide with an interesting proposition. With hopes of reinvigorating business at the bar, Otis convinces a skeptical Herrmann to throw a bash in celebration of the milestone 100th anniversary of Molly's, but not without complications.

Dawson and Casey deal with legal matters in hopes of remaining Louie's legal guardians. Severide continues in his efforts for a bone marrow procedure to help Anna, but when things don't go as planned, he finds himself slipping back into old habits. Meanwhile, Brett opens up to Dawson and members of Firehouse 51 become competitive, much to the dismay of Chief Boden.

The crossover continues on Chicago P.D. S04E09 Don't Bury This Case (II).

Severide agrees to a bone marrow donation but a work accident throws everything into flux. Casey and Dawson try to find harmony at home. Meanwhile, Otis and Mouch decide to film a PSA encouraging people to join the Chicago Fire Department but hit a creative wall in the process.

Dawson finds it hard to keep her emotions in check during an ambo run involving a pregnant teen. Elsewhere, the firehouse is called to the site of a building fire and Casey is forced to make a split-second decision when two victims are each need of life-saving assistance. In the aftermath, Casey is left to deal with the repercussions. Meanwhile, Severide shares a bond with Anna, as she makes her recovery.

The team is on high alert when a previous incident during a fire call leaves a dangerous man on the loose with a vendetta to target Lt. Casey and Firehouse 51, and prompts CPD to step in. Dennis Mack, a buddy firefighter of Severide's father, comes to town to shadow the squad but may have ulterior motives. Meanwhile, Brett and Antonio's relationship hits some bumps in the road when his ex-wife Laura surfaces and Casey has a present for Dawson.

When truck and squad are summoned to the scene of a dangerous accident, Chief Boden makes a split-second decision that overrides Chief Anderson, the incident commander whose house was the first to respond to the call. Feeling his authority was undercut and his reputation damaged, Anderson uses his power to make things miserable for Boden and all of House 51 feels the repercussions.

After exercising his disdain and authority over Chief Boden, Chief Anderson reassigns members of 51 to various houses around town, citing the need for improvement. The ramifications are felt by the crew, who are left to make the best of their respective situations in their new surroundings.

Truck and squad are called to aid in a massive all-city response when an old, ill-equipped factory-turned live/work space quickly turns into a firestorm, trapping countless unsuspecting victims. The dire situation quickly turns personal when it is discovered that one of Chicago PD's own has a family member at the scene.

The crossover continues on Chicago P.D. S04E016 Emotional Proximity (II) and Chicago Justice S01E01 Fake (III).

When a turf war escalates, members of truck and squad find themselves caught in the middle as unsuspecting hostages when a group of armed gang members take cover and assume control over Firehouse 51.

When similar car accidents uncover the fact that someone may be targeting innocent people, a determined Dawson takes matters into her own hands to help push things along. Severide does everything he can to make Anna feel welcome in her new Chicago surroundings. Herrmann, Kidd and Dawson decide to have Molly's included as a stop in this year's pub crawl. Meanwhile, Casey tends to his Alderman's duties when a persistent constituent asks for his help in resolving an issue.

Casey discovers a new crack house on the block that is harboring a female junkie. Dawson and Brett get assigned a new trainee for the shift. Meanwhile, Severide gets an unexpected visit from his father and Herrmann deals with family issues when his son gets into trouble at school.

When the squad's rig breaks down in the field, Casey reunites with his old friend and colleague Jason Kannell from Squad 6. Dawson and Brett serve their time in retraining. Severide tries to remedy what is going on with Anna and finds support from unlikely sources. As Connie returns from her family engagement, the crew lays bets on how long her temporary replacement Marcy will last.

Casey goes to drastic measures to help his friend Kannell. Lt. Severide helps an old widow come to terms with letting go, but realizes he may be the one needing help. Otis and Cruz deal with surprises when they find a new roommate to move in. Dawson and Brett get crafty to save a young girl.

Cruz finds himself in a bad spot when an off-duty incident begins to unravel, prompting Mouch to step in and offer help in hopes of avoiding serious consequences from the CFD. Casey goes head to head with a big politician to get his measure for first responders passed. Lt. Severide makes life difficult for newest team member Jason Kannell and Dawson gets an unexpected visit from her father.

A dangerous warehouse fire puts truck and squad at risk. Tensions are high for Dawson and Casey when Dawson's father overstays his welcome at their home. Meanwhile, Casey continues to fight for his first responders bill, Mouch makes a serious decision regarding his future and Herrmann goes to tremendous lengths to make a young boy smile.

With most of the squad still trapped inside the burning warehouse fire, Chief Boden makes a risky last-minute decision in an effort to save his men. Dawson continues to deal with her father, who has new plans for himself. Brett's childhood friend Hope visits the Windy City and strikes the attention of someone within the firehouse, while Kidd goes head-to-head with her landlord. Meanwhile, a fire at a high school hits close to home for Boden.

After learning the school fire wasn't an accident, Chief Boden turns up the pressure on Severide and Casey to investigate the cause of the fire that trapped his wife. Fueled by a competitive bet against Firehouse 87, Mouch pushes all of the wrong buttons in his need to win the competitive challenge known as the firefighter muster. Meanwhile, as Kidd settles into her new living arrangement, her unresolved feelings prompt her to question the intentions of newcomer Hope.

Lt. Casey gets off on the wrong foot with Sam Mullins, a temporary Chief who is filling in for Boden at House 51 for the morning. When Casey later makes a risky move in an attempt to save a distraught man from jumping off a building, Mullins has a surprise that Casey does not expect. Mouch flies in Cruz's brother Leon as a birthday surprise, but the rest of the squad struggles to keep it a secret. Meanwhile, Brett is caught off guard when she learns new information about her hometown friend Hope.

While running a secret errand, Dawson finds herself trapped in a collapsed parking structure. With all paths of exit blocked, she is forced to improvise and works double-duty to keep a number of injured individuals alive while trying to maintain peace among those trapped. Meanwhile, pressure is mounting on Casey as he begins to take on additional duties, Kidd grows increasingly skeptical of Hope after learning about rumors circulating and the firehouse receives a surprise visitor.

Casey and Severide find themselves at odds after Casey argues with him over the best way to save a teenager entangled in barbed wire. When Casey looks to Boden for help smoothing out the situation, he comes to the realization that he will have to fix it himself. Elsewhere, Otis tries to convince Casey to participate in the beta test for an expensive piece of new firefighting equipment imported from Japan. Meanwhile, Kidd and Hope come to blows over a payroll issue and Brett goes on a date with a doctor she meets during an ambo call.

After heroically saving a mother and newborn baby from a rooftop fire, Kidd receives surprising news when she discovers she is being transferred out of the firehouse. Severide and Casey believe something is off about the turn of events, prompting them to investigate the situation. Otis and Herrmann discuss the possibilities of taking over a rundown bar and Dawson's frustration with her father, Ramon, reaches a boiling point.

Brett attempts to make a lifesaving decision in the field to someone near and dear to the firehouse family. In an effort to impress Lily, Otis scrambles to get everything together for the grand opening of Molly's North. Meanwhile, Boden becomes emotional following the rescue of a famous blues player from a burning apartment building and Dawson struggles to come to terms with how she has been dealing with her father.

After saving a young girl, Dawson is forced to make a tough decision when she finds out the girl's father is addicted to painkillers. Herrmann loses his cool and gets into an altercation with a police officer after responding to a call. Otis and Cruz are on a mission to find out who Brett is dating. Meanwhile, Boden is skeptical when Donna's brother Julian unexpectedly comes to town.

After learning unsettling news, Dawson enlists Severide to help her out. Elsewhere, Casey and Dawson struggle with communication issues while Brett and Kidd compete to win the heart of Zach, a Hazmat officer. Meanwhile, Otis, Herrmann and Mouch are on a mission to locate the source of a horrible stench that is making life unpleasant at Firehouse 51.

Dawson and Casey do everything they can to locate Bria's whereabouts after discovering important new information. Lt. Severide reunites with Chief Grissom, and old family friend. Meanwhile, Cruz enlists the help of Brett and Mouch to create a new tool and Kidd and Zach go on a date.

After responding to a time-sensitive rescue, Casey and Severide don't see eye to eye on the best course of action. Herrmann struggles to entertain his daughter on "bring your child to work day." Brett is joined by a surprise guest during a spa getaway, courtesy of Dawson, while Kidd's social life gets a boost.

After photos of Casey and Severide jumping off the roof during a heroic rescue make the front page of the newspaper, Boden unwillingly agrees for the photographer to chronicle a day-in-the-life story at the Firehouse. Dawson and Brett are on a mission to find out what keeps happening to Gerald, a frequent flier they know who lives on the streets. Meanwhile, Herrmann decides to take up life-coaching as a side job and Kidd makes a decision regarding her living arrangement with Severide.

While working to track down a bombing suspect, Voight and Antonio meet with Chief Boden, who unwillingly agrees to let Dawson and Brett go undercover. As the investigation continues, Boden, Casey and Severide lend their skilled expertise in the investigation. Elsewhere, Kidd and Zach's relationship hits a bump and Cruz has a hard time expressing his true feelings for Brett. Meanwhile, Herrmann and Connie are forced to come up with an alternative solution when two birthday parties are booked on the same day at the firehouse.

The crossover starts on Chicago Fire S05E016 Profiles (I).

After responding to a car accident, Casey and Dawson become skeptical when a domineering husband continues to answer for his injured wife. Cruz becomes frustrated with Herrmann and Mouch when he discovers they have contacted people regarding his "Slamigan" invention without his knowledge. Kidd uncovers something meaningful and important to Severide while Brett discovers some potentially unsettling news.

In response to a call involving a residential fire, Otis and Kidd's lives are suddenly put in jeopardy when gunfire goes off inside the house. Dawson comforts Brett during an especially trying time. Meanwhile, Casey begins to notice that romance might be going on within the firehouse.

The crew struggles to come to terms with an injury to one of their own; a temporary replacement must be dealt with; Boden ponders some interesting news; Kidd has a hard time keeping a secret.

Boden has a lapse in judgment in the aftermath of rescuing a young boy. Kidd struggles to win the approval of Severide's mom after a surprise visit and Otis takes on new responsibilities at the firehouse.

When the FBI takes over Firehouse 51 for an undercover mission, Casey and Severide volunteer to assist with the investigation. Kidd attempts to help Severide come to terms with recent developments he's been managing.

After responding to a residential fire at a property belonging to a Mexican drug cartel, Casey is skeptical of Cordova after a hefty amount of money was found missing from the crime scene. Elsewhere, Kidd makes a big decision.

After saving a girl from a car accident, Chief Boden and Lt. Severide are taken aback when they receive a surprise package. Brett struggles to keep quiet about Cruz reacquainting with his now-married high school sweetheart and Otis tackles his next challenge. A crisis brings Bria back into Dawson's life.

Lt. Severide is shocked when Rene Royce resurfaces; Casey comes up with a plan to help Chief Boden in his latest pursuit; Kidd regrets a decision she made regarding Severide; Herrmann clashes with Lt. Colannino over their son's basketball team.

Boden takes a big step in the pursuit of a major career decision. Kidd becomes increasingly distrustful of Renee's motives with Severide. Herrmann has trouble bouncing back after a tragedy.

Boden's chances for a promotion are met with potential complications. Dawson and Casey don't see eye to eye on an important decision, while Kidd finds herself struggling to find time with Severide. Brett and Dawson respond to a tough call that quickly turns dangerous.

Casey tries to deal with his unsettled personal life and the firehouse welcomes a new member. Boden clashes with new Assistant Deputy Commissioner Jerry Gorsch.

Firehouse 51 is faced with a daunting challenge when an out-of-control blaze consumes a 15-story apartment complex, trapping victims on the top floors. Complicating the rapidly escalating situation, members soon discover that someone close to home may be one of the trapped victims.

The crossover continues on Chicago Med S04E02 When to Let Go (II) and Chicago P.D. S06E02 Endings (III).

Chief Boden becomes increasingly skeptical of Assistant Deputy Commissioner Gorsch's motives, while Severide gets wrapped up in a difficult situation following the rescue of a child from a car wreck. Trying to fit in with the rest of the firehouse, Foster is tasked with doling out some personal advice to Cruz.

Nenhum trabalho é tão perigoso e emocionante como o dos bombeiros e paramédicos do Quartel 51 em Chicago. Arriscam a vida quando todos tentam salvar-se e, mesmo quando a pressão obriga a decisões rápidas e divergentes, na hora de agir são uma equipa.

Working alongside a journalist, Casey does some digging into the cause of a trailer park fire. Boden hits his breaking point while Mouch, Herrmann and Cruz work to figure out why Molly's isn't performing up to expectations.

Halloween is in full effect for Foster and Brett, who are summoned to a home where a prank has quickly turned serious. Gorsch continues his reign of terror on Firehouse 51.

Severide faces some major adversity and Kidd is on a mission to help in any way she can. Following a car accident rescue involving a teenage girl and her young sister, a suspicious Brett has an unsettling feeling there is more to the story than what appears on the surface.

Firehouse 51 is called in to battle a dangerous structure fire that places everyone in peril. Severide makes a big personal realization. Casey lends another helping hand to Naomi, the investigative reporter.

Stakes are high when a massive car pile-up on the freeway impacts someone dear to the firehouse family. Brett and Foster encounter a harrowing call while Kidd and Severide find their relationship being tested.

A dangerous situation leaves Casey and Naomi in peril. Foster and Brett are in charge of planning a field trip visit to the station while Severide and Kidd go through tough times.

Foster faces blowback after pointing out a doctor's oversight. Brett helps Casey look for a new apartment. Kidd prepares Tuesday the Dalmatian for the Fire Safety Dog Competition. A serious accusation is leveled against Severide.

When the firehouse is called to a motorcycle crash, Casey and Severide sense that the details don't add up and work to determine exactly what transpired. A rift develops between Mouch and Otis. Brett, Foster and Kidd work to secretly fix a dent in the ambulance bumper they believe they unknowingly caused.

Cruz leads the charge in getting the firehouse to gear up for the Polar Plunge. Herrmann has a hard time bouncing back after dealing with a tough call. Foster's personal relationships begin to interfere with her job.

Brett, Foster and Kidd take a road trip to Indiana and encounter an accident involving a boys' hockey team that leaves them scrambling and relying on their instincts to save the injured. The rest of Firehouse 51 competes in the annual chili cook-off.

A spate of robberies comes to light after a firehouse lockbox key goes missing; Sergeant Hank Voight suspects a firefighter may be involved, and with Boden's support, he recruits Cruz to go undercover to help sniff out any suspicious activity.

The crossover continues on Chicago P.D. S06E15 Good Men (II).

Casey struggles after experiencing a narrow miss on a call. Otis wins a unique sporting opportunity in a raffle. Grissom turns to Severide for assistance when the mayor's office sends a task force to Firehouse 51.

Tensions run high between Casey and Herrmann after the firehouse responds to an apartment complex fire. After discovering something extremely suspicious during the call, Kidd and Severide do some investigating and get CPD on the case.

Severide gets angry at Cruz when he feels his orders were disobeyed in the field. Boden reconnects with an old high school friend during a call to a house fire. Herrmann has issues when one of his favorite knick-knacks from Molly's goes missing.

A horrible storm wreaks havoc on Chicago and impacts Firehouse 51 when the power goes off. A little boy mysteriously shows up at the station and everyone works together to uncover who he belongs to. Foster and Kidd argue about Severide.

Severide and Boden search to uncover whether arson was the cause of a fire at a hair salon. Mouch, Herrmann, Otis and Kidd make a startling discovery in tracking down the missing piercing nozzle from Engine 27.

A serial arsonist cold case is reopened when Lt. Severide finds a connection to a recent salon fire. Firehouse 51 celebrates a retirement party.

Severide and Kidd continue to investigate Benny’s old arson case, unexpected news leads Brett to ponder a big decision and all hell breaks loose.

The mattress factory fire spirals out of control. Truck and squad lay it on the line in hopes of getting the trapped victims out alive.

Lt. Casey struggles to get Chief Boden to sign off on an energetic new recruit. Against her better judgment, Foster extends an olive branch to her irritating new medic. Otis inspires Herrmann to seek new partners at Molly’s. Brett realizes life in Fowlerton will take some getting used to.

Brett and Foster question the suspicious circumstances surrounding a brutal attack at a juvenile detention center, which leaves them searching for the truth. A convoluted new technology installed inside Firehouse 51 tests everybody’s patience. Kidd gets chosen to represent the district at a leadership conference.

A rare but deadly bacteria takes its toll on numerous victims around the city, leaving Chicago’s finest first responders to work together alongside the CDC to resolve the dangerous situation. Following a fire at a local university that ties into the outbreak, Severide has suspicions that something bigger is happening.

The crossover continues on Chicago Med S05E04 Infection, Part II (II) and Chicago P.D. S07S04 Infection, Part III (III).

Kidd must prove herself at the National Firefighter Leadership Conference while the rest of Firehouse 51 is called to two eerily similar car wrecks. Mouch tries to keep everyone in the firehouse informed by starting a newsletter, but things quickly get out of hand. Cruz deals with a heartbreak.

Cruz and Severide suspect foul play when a fire started by an elderly woman turns deadly. Kidd, Foster and Brett create a women’s-only lounge. Firehouse 51 celebrates some good news.

Severide must make a tough decision about the future of his career at Firehouse 51. Herrmann deals with the consequences of his temper. Cruz is excited to demonstrate the Slamigan at the Firefighting Expo. Commissioner Grissom returns.

Severide begins his assignment at the Office of Fire Investigation and gets off on the wrong foot when, despite his orders, he reopens an old case. When the cause of an apartment fire hits close to home, Herrmann is on a mission to get to the bottom of it. Kidd finds herself burning the candle at both ends.

An unexpected visit throws Casey for a loop. Severide sets out to exonerate a wrongly convicted arsonist. Kidd pays the price for burning the candle at both ends. Cruz goes on a mission to fix one of Otis’s old toys.

Members of Firehouse 51 are dismayed to learn their boundaries have been redrawn to overlap with an adjacent station and problems quickly arise. Casey and Gallo hunt a missing piece of equipment. Brett and Foster find themselves at odds. Mouch tries the find the recipient of a mysterious letter he discovers.

A pest control problem forces the 51 team to temporarily bunk with Firehouse 20. All under the same roof, Casey clashes with Capt. Delaney while Foster, Kidd and Brett fear Capt. Leone has it out for them. Boden mulls a procedural overhaul.

A series of false alarms at a private school hinders the firehouse's ability to respond to legitimate emergency calls. Kidd asks for ideas to surprise Severide on his birthday. Cruz and Brett rent out their extra room, but the new tenant is more than they bargained for.

The surprising arrival of a new fire truck brings both joy and chaos to members of Firehouse 51. Boden and Severide are asked to make peace with an old foe for the greater good. Brett receives family news while Foster plans a party with friends.

A series of mysterious gas leaks has members of Firehouse 51 puzzled and spread thin. Brett’s conflicted when her birth mother gets serious about tracking her down. Severide misunderstands his role as Cruz’s best man. Mouch bites off more than he can chew.

A series of teen opioid overdoses sees Severide partner with Sean Roman, but begins to suspect there’s more to the story than his old friend is telling him. Casey tries to be there for Brett as she considers her birth mother’s offer to meet.

The crossover continues on Chicago P.D. S07E15 Burden of Truth (II).

Boden is on edge after starting a new fad diet. Casey and Severide disagree on a call. Brett’s birth mother shares life-altering news. A familiar face has a proposition for Herrmann.

Things get personal for Casey and Gallo in the aftermath of a suburban house fire involving a mother and her young son. Herrmann campaigns for more respect. Kidd has an idea for giving back to her community.

Lt. Severide teams up with Seager and the OFI when a motel structure fire turns suspicious. Firehouse 51 members become amateur sleuths following a Reddit post involving one of their own. Brett continues to get invested in her birth mother, Julie.

Tension builds when a group of rabble-rousers attempt to lock down the firehouse. Brett is faced with a monumental decision. Cruz readies himself for a big day. Gallo and Ritter attempt to launch Firehouse 51 into the social media age.

When one of 51's own gets injured on a call, Lt. Severide becomes obsessed with helping out. Foster contemplates a big decision. Kidd is concerned for one of her high school trainees.

Firehouse 51 welcomes a new member to the team, whose presence could provide some complications. Brett's leadership shines during a scary call. Boden sees great potential in Kidd and proposes an idea that could have lasting repercussions.

Brett and Mackey find their lives in peril. Casey and Brett tread in unfamiliar territory. Severide chases a memory while Kidd adeptly solves a firehouse problem. Ritter puts himself in harms way during a harrowing call.

A mishap on the aerial ladder in the midst of a fire rescue leaves Mouch shaken and questioning his abilities. Kidd looks for support from Severide while Casey and Brett discuss their future.

While completing a task assigned by headquarters, Boden makes an unforeseen connection. Gallo is forced to make a surprise rescue to one of their own when the firehouse is called to the site of a construction explosion. Mouch reignites an old feud.

When Firehouse 51 is called to the scene of a dangerous blaze inside a 10-story storage unit, Herrmann and Cruz find themselves trapped inside a freight elevator with all communications cut off.

Gallo makes a split-second decision during a dangerous fire rescue leaving Casey steaming that his direct orders were not obeyed. Kidd feels a strain in her relationship with Severide. Brett and Mackey find themselves searching for answers following a series of suspicious calls.

A fire at a homeless encampment leaves Severide and Casey searching for answers. Cruz is shaken up after a close call. Ritter lends a helping hand to a victim.

A call to a familiar location brings back mixed emotions for Severide. Herrmann heads out for a vacation. Casey is not thrilled with his replacement.

Mouch, Gallo, Ritter and Mackey report for training. A nasty blow to the head brings Casey unimaginable pain.

A series of suspicious fires sends 51 on a search for the cause. Casey continues down a troubling path. Mouch is looking to make his long-awaited dream come true.

A new recruit with ties to the CFD tests Serveride's patience. Violet receives a mysterious note that sends her and Brett on a hunt for the person who wrote it.

While Mouch makes an incredible save, all eyes are on a mystery man who helped save his neighbor. Casey worries about his future at the CFD.

A mysterious caller who is in danger relies on Kidd to help save her and her brother. The firehouse helps Cruz get ready for fatherhood.

A fire breaks out at a pet food factory and Casey and Severide help the owner, Pete, get to the bottom of it. The annual garage sale takes place at 51 and everyone is on edge.

Severide and Casey try to find the best fit for Kidd. Ritter, Gallo and Violet help plan an event for Mouch.

The firehouse reacts to some exciting news, a mysterious stranger arrives and a shocking call takes Severide's breath away.

O Firehouse 51 lida com as consequências do resgate do barco virado. Gallo, Ritter e Violet discutem planos para um show paralelo.

Um vídeo de Casey do resgate do telhado se torna viral. Mouch monta uma pequena biblioteca gratuita no Quartel 51. Herrmann quebra o protocolo.

Griffin descobre a verdade sobre a morte de seu pai e revela por que ele realmente veio visitar Casey. Gallo, Ritter e Violet tomam medidas para expandir seus negócios de microcervejaria.

Kidd abre suas asas como tenente. O chefe Hawkins viaja com a ambulância 61 para aprender mais sobre Brett. Casey faz uma viagem para fora da cidade. Uma noite de encontro Ritter se transforma em uma situação de emergência

Casey toma uma decisão que muda sua vida. Gallo, Ritter e Violet concordam com uma entrevista e sessão de fotos. Brett e Mouch lançam o programa de paramedicina. Cruz se aproxima da paternidade.

Uma grande violação de segurança nas redes de computadores da cidade obriga os líderes seniores do Firehouse 51 a resolver o problema por conta própria. Severide se prepara para uma investigação de incêndio criminoso.

Gallo entra em conflito com o novo tenente temporariamente substituindo Casey. Severide se aproxima de um incendiário perigoso e mortal.

Severide e Herrmann brigam por espaço de escritório. Boden olha para o passado de Pelham enquanto pensa em torná-lo permanente. O ressentimento de Gallo por Pelham vem à tona. Brett e Ritter forçam Violet a confrontar seus verdadeiros sentimentos por Gallo.

Gallo, Violet e Ritter estreiam seu negócio de microcervejeira no Winterfest. Brett se prepara para apresentar seu programa de paramedicina a um painel de supervisão. O Quartel 51 entra no espírito natalicio.

Stella Kidd returns to Firehouse 51. The team must work together to put out a potassium fire in a tunnel. After that incident, Ritter begins to worry about a young cop who witnessed the fiery death of a truck driver.

On a call with Station 37, a firefighter is struck by a power line and decides to lash out after her injury. Brett is visited by Scott and Amelia. Violet gets a surprise envelope. The rest of 51 enters a contest.

Boden, Kidd and Severide work together to protect one of their own. At the Fire Academy, Herrmann meets an inspiring young man. Talk of the annual CFD Gala dominates the firehouse.

Severide and Seager team up to investigate a fire at the home of a troubled young woman. Pelham moves into 51's rumored cursed office. Kylie assists Kidd with Girls on Fire.

Chief Hawkins goes above and beyond to help Brett and Violet with a problem. Kidd pursues an open lieutenant position. A blast from the past asks Mouch and Herrmann for a favor.

Following an injury in the aftermath of an industrial fire, Severide and Seager work together to investigate an anonymous tip. Kidd searches for the right person to fill the opening on Truck 81.

Cruz forms a bond with a young immigrant boy he meets while fighting an apartment fire. Squad makes plans to prank the newest member of their team.

Severide and Kidd work with CPD regarding a suspicious car wreck. Hawkins and Violet's relationship is in jeopardy. Chloe and Cruz adjust to a new family dynamic.

Firehouse 51 must band together when one of their own is taken hostage.

Firehouse 51 tackles a fire caused by a dropped jet engine, and one of their own is accused of a theft related to the incident. Kidd and Boden disapprove of Kylie's potential new love interest.

A family friend asks Herrmann for some advice on opening a bar. Tensions run high between Emma and Violet. Kidd struggles to keep her team together.

Mouch and Ritter work together to solve a murder mystery. Severide and Cruz tackle a food truck fire. Gallo goes to see Hawkins about Violet.

The big wedding day arrives and Firehouse 51 welcomes Casey back to celebrate the joyous occasion. Emma's plans to replace Violet come to a shocking end.

Kidd and Severide's honeymoon is interrupted by a dangerous person from their past. Kidd's former academy classmate joins Firehouse 51. Brett and Violet reflect on their relationships.