Os habitantes da Cauda planeiam a sua próxima rebelião. Melanie, a chefe da Hospitalidade, recruta Layton, o líder dos Caudas, para ajudar numa investigação.

Alguns Caudas são castigados pela tentativa de rebelião, Layton e a Guarda-freio Till analisam os detalhes do primeiro crime e o comboio sofre um acidente devastador.

Layton quer falar com Nikki e investiga o passado de Sean. Melanie e Roche descobrem mais sobre o Kronole. Para acalmar os passageiros, é organizada uma distração.

Depois de outro crime, intensifica-se a caça pelo suspeito. Layton e Melanie vão até à frente do comboio para fazer interrogatórios. Os Caudas querem saber de Layton.

O julgamento de uma suspeita dos homicídios leva a uma revelação surpreendente, Till celebra um marco importante, e Josie esgueira-se para ir procurar Layton.

Enquanto a Terceira Classe se prepara para protestar contra o veredito do julgamento e Layton tenta recuperar, Melanie tem de lidar com uma emergência inédita.

Temendo que se descubra um segredo obscuro sobre o comboio, Melanie procura Layton. Josie quer ver Miles, e Ruth tem um encontro inesperado.

Enquanto a Primeira Classe confronta Melanie sobre quem está à frente do comboio, Layton e os outros conspiradores elaboram um plano para chegarem à Locomotiva.

O Comandante Grey, Ruth e os Folger preparam um ataque contra os rebeldes. Layton descobre uma verdade chocante. Presa, Melanie aguarda o seu destino.

Uma nova liderança vem agitar as águas a bordo do comboio. Uma surpresa enche alguns passageiros de esperança, mas instila medo noutros.

Mr. Wilford arrives and threatens Snowpiercer, so Melanie makes a move that can't be undone.

An exchange is made between the two trains, but a far greater revelation might be just over the horizon.

Melanie embarks on her most dangerous mission yet, while Layton reckons with his personal choices.

As the Big Alice crew are granted shore leave on Snowpiercer, Layton and Wilford have differing opinions on the future.

Layton and Miss Audrey make a risky play for Big Alice, but Wilford has his own plans.

Melanie fights for survival in treacherous conditions, vying to do what others before her could not.

Layton and Till investigate the murders. Wilford leads Miss Audrey down a dark path.

An engineering catastrophe on Snowpiercer forces Layton to make a difficult choice, one that might cost him everything.

Wilford presses forward on his endgame while those who are close with Layton grow anxious to learn their fates; Josie tests her newfound ability.

As the train approaches Melanie's retrieval point, Layton leads a furious attempt to try and pick her up but not without some sacrifices.

While Wilford emphasizes his rule aboard his icy train, Layton's pirate train continues its dangerous quest for warm spots, and comes across something entirely unexpected.

Layton goes on the hunt, as Wilford works to boost morale. The resistance discovers a threat that could undermine everything they've worked for.

It's a game of cat and mouse as both Layton and Wilford vie for the upper hand.

Alex must finally deal with her parental figures as a track obstruction uncovers a painful past.

A series of terrorist attacks threatens to derail Layton and Zarah's big day.

As the bomber is revealed, Layton comes to terms with his past decisions before making an irreversible call.

Layton realises some dreams are out of reach. As the rest of the train deals with Layton’s status change, Wilford makes a staggering discovery.

As the train detours from New Eden, an environmental catastrophe threatens everyone onboard.

Reunited with old friends, the train throws a party. Alliances are tested as the truth is finally revealed.

It all comes to a head as old adversaries clash, with New Eden hanging in the balance.