Detective Beckett fights for her life as Castle, plagued by guilt over his role in the events, struggles to uncover who's behind her brutal shooting. Meanwhile, back at the precinct, Ryan and Esposito have to adjust, as Victoria "Iron" Gates becomes the precinct's new uncompromising Captain.

When an ex-con is mysteriously slain in an alley, Castle and Beckett believe a vigilante is behind the murder. But efforts to identify their suspect are thwarted when they discover that he roams the city in a Superhero costume – and may indeed be a Superhero. Can they capture and unmask the killer before he strikes again?

A murder scene complete with lots of blood but no victim and high tech life-extension science are all part of the investigation as Castle and Beckett try to solve a murder without a body. Meanwhile, Alexis waits to hear news about her application to Stanford

While investigating the mysterious shooting death of a young woman, Castle and Beckett face a cop's worst nightmare when they discover that the gun used in the killing is Det. Ryan's old service weapon - the one that was stolen by the serial killer, 3XK. Now with the clock ticking, the team must work to solve the murder, track down 3XK and retrieve Ryan's gun before the killer strikes again.

A wealthy museum patron is a suspect when a valuable sculpture is stolen. Castle and Beckett investigate the theft with the help of an insurance investigator who sets her sights on Castle.

While doing some investigative work at a New York mansion, a prominent ghost hunter is murdered. Castle and Beckett must figure out if paranormal activities are to blame.

A crew of bank robbers disguised as classic television doctors take hostages which include Castle and Martha. But things are complicated by the fact that Beckett's on the outside having her every move scrutinized by a hostage negotiator and Castle's on the inside with information that the hostages are just a distraction for a more ominous plan.

During the investigation of the murder of an Atlantic City casino owner at an abandoned warehouse, strong leads emerge for the team in both New York and Atlantic City. As Beckett and Capt. Gates work the New York leads together, Castle naturally chooses to join the detectives for the road trip to "America's Playground," hoping to help solve the case while throwing an impromptu bachelor party for Ryan.

A sniper on a killing spree is terrorizing New York City. With the clock ticking down to the next murder and nothing to go on except a killer with no apparent motive but to instill terror, this could prove the team's toughest case yet. The hunt is made even more complicated when Beckett begins to experience increasingly strong moments of PTSD - moments she tries hard to hide from Castle and the detectives.

When Castle and Beckett wake up in bed, handcuffed together, in a locked room with no memory of how they got there, they must piece together the mystery of where they are and why, all while trying to escape. But as the two of them adjust to being shackled together, what's the biggest threat they face... the people who abducted them or each other? Meanwhile, Ryan, Esposito and Gates are left to investigate their disappearance in a case where all is not what it seems.

When a lothario is killed, Castle and Beckett suspect that the victim’s mysterious double life holds the key to his murder. Their investigation leads to a shocking twist that threatens to disrupt Ryan’s wedding with Jenny

It was longtime Castle friend Mayor Weldon's political clout that allowed Castle to partner up with Beckett. But now, when a woman is found dead in a car that traces back to the Mayor's motor pool, that partnership comes under fire as the scandal surrounding the investigation threatens to bring down Weldon's administration.

When a famous dog trainer is killed, the investigation keeps coming back to charismatic reality TV star Kay Cappuccio. Kay, a favorite of tabloids and gossip websites the world over, has achieved stardom without possessing any discernible skill or talent. But there seems to be more to her story than she is letting on -- does that include murder?

When Castle and Beckett investigate the killing of a treasure hunter, they discover the case is linked to a mysterious homicide from 1947 involving a hard-boiled private detective. Castle realizes the only way to solve the present-day murder is to solve the murder from the past. The 1947 case comes to life through stylized flashbacks, featuring Castle as the private eye and Beckett as a femme fatale.

Castle and Beckett pursue a ruthless killer who, they discover, is part of a sinister, international conspiracy. Castle and Beckett are joined on the case by Sophia Conrad, a smart, sexy CIA operative who has a complicated past with Castle.

Castle & Beckett race to find the "Linchpin" in order to stop the first domino in a chain of events which will plunge the United States into war. Their efforts continue to put Castle in contact with Sophia Conrad - a smart, commanding and sexy CIA operative who was Castle's inspiration for Clara Strike in the "Derrick Storm" series of books; and intelligence officer Martin Danberg is back.

When a woman dressed as Red Riding Hood is found dead in the woods with claw marks covering her body, and soon after a murdered Snow White is discovered with a poison apple in her hand, Castle & Beckett find themselves on a Grimm hunt to catch a fairytale killer before he kills again. But nothing is as it seems in a case filled with deceit, betrayal, secrets and murder

When Odette Morton, a contestant on the hit competition show “A Night Of Dance,” is found murdered in her dressing room, Castle and Beckett must navigate the case’s many twists and twirls without stepping on each other’s toes. But as they delve into Odette’s past, they discover that this reality starlet was harboring a shocking secret that may have led to her death

When a bomb explodes at a protest rally killing five people, Castle and Beckett realize the key to solving the case is to reconstruct the 47 seconds prior to the explosion. Using video and witness accounts, they uncover the shocking truth about who planted the bomb.

A devilishly handsome detective from Scotland Yard, Simon Hunt, teams up with Castle & Beckett to find the person responsible for the murder of his friend's daughter. Also, Nigel Wyndham, the Deputy General at the British Consulate whom Castle & Beckett suspect is up to more than just ambassadorial balls and diplomatic luncheons. Meanwhile, Lanie convinces Beckett that she needs to make a move on Castle before it is too late.

With tensions rising between Castle and Beckett, Castle finds himself a new partner -- Detective Ethan Slaughter (guest star Adam Baldwin, "Firefly"), a tough and colorful cop from the city's gang unit. But Castle gets more than he bargained for when Slaughter shows him a grittier side of police work that puts Castle in the line of fire like never before

When Castle and Beckett investigate the murder of a man with human bite marks on his body, Castle's wild theories start flying. But none are as wild as what their only witness insists happened - a Zombie attack. As the evidence pointing towards an undead assailant piles up, the team plunges into New York's Zombie subculture to find the killer and bring him in -- dead, undead or alive

When the murder of an Army veteran puts Beckett on the trail of the man who shot her, Castle must decide how much he's willing to sacrifice to keep her safe. As secrets are revealed and feelings are put on the table, the lives of the detectives at the 12th Precinct may never be the same.

Picking up the morning after, Castle and Beckett now have to decide if they're a couple or was it just a onetime deal. But before they can tackle that, they must deal with those responsible for Kate's mother's death who are now a threat to Beckett.

On Beckett's first day back from her suspension, she and Castle are thrown into the salacious world of local TV news when WHNY's veteran weather girl is found dead. As if navigating an industry full of backstabbing and ruthless ambition weren't difficult enough, they have to do it while hiding their new relationship from their coworkers

A repossessed storage unit, treasure seekers and Manhattan socialites all come together in the case of a woman inexplicably murdered. Castle decides to enter the storage unit auction to see if anything inside might have led to her killing.

Castle and Beckett’s plans for a romantic weekend in the Hamptons are interrupted when a dying man stumbles into Castle’s backyard, collapsing into his pool. Unable to escape the lure of the investigation they join up with the small town’s well-intentioned, but inexperienced sheriff to find the killer,

While investigating a shocking ritualistic murder, Beckett and her team uncover surprising evidence linking Castle to the killing. As the evidence against him mounts, loyalties are tested. And when surprising revelations come to light, Beckett begins to wonder how well she really knows her new lover and partner of four years

When a body is found at a sci-fi convention, Castle and Beckett are warped into the heart of fandom -- a world of egotistic celebrities, diehard costumed fans and enough drama for two galaxies.

A documentary crew follows Castle, Beckett and the team as they investigate the murder of a rock band's lead guitarist.

In the aftermath of a disastrous "Meet the Parents" dinner, a bickering Castle and Beckett are sent to retrieve the only witness to a murder, but they get ambushed and are forced to take the witness on the run. Stranded in the middle of the night in a bad part of town, with no phone, badge or gun, Castle and Beckett must find a way to protect him from a team of mobsters -- that is, if they don't kill each other first.

Castle and Beckett investigate when a bearded man named Kris Kringle falls from the sky in Central Park; Beckett and Castle work on a Christmas list together.

When a powerful divorce attorney who only represented women is murdered, Castle and Beckett are confronted with a plethora of angry ex-husbands, any one of whom could be the murderer. Meanwhile, Castle's ex-wife (Darby Stanchfield), Meredith, moves into the loft to take care of Alexis while she recovers from Mono, and to make matters worse, Beckett is also forced to move in while her apartment is being fumigated, causing tension, humor and more than a little awkwardness

When an up and coming DJ is killed at a pop star's album release party, Beckett and Castle must dive into the raucous world of New York's music industry. Then, when the investigation leads to a troubled teenager, Esposito takes the kid under his wing, hoping to put him on the right track before it's too late.

When Beau Randolf, the founder of hit adult video franchise "College Girls Gone Crazy," is murdered, Castle and Beckett are confronted with a lengthy list of husbands, fathers and ex-college girls who all have motive. So to find the killer, they must delve deep into the victim’s life, where they find surprises at every turn. Also Alexis starts a video blog, but Castle is not happy that personal and intimate details about her life are being made public.

While investigating the murder of a young woman, Castle and Beckett find evidence that links her death with Senator William H. Bracken (Jack Coleman), the man responsible for Beckett's mother's murder. Determined to finally bring Bracken to justice, Beckett soon realizes that things are far more complicated than they seem.

Castle & Beckett get an up-close-and-personal view of a "Real Housewives"-esque reality TV series, "The Wives of Wall Street," when they investigate the murder of the show's rising young star. Meanwhile, Castle's attempt to give Beckett a Valentine's Day gift goes horribly wrong.

In the first of a two-episode story arc, Castle and Beckett begin a murder investigation that also exposes a plot to kidnap the daughter of a wealthy Middle Eastern businessman. FBI Agent Harris, an even-keeled professional is brought in to help find the kidnappers.

In the powerful conclusion of a two-episode story arc, when the FBI fails to get his daughter back, Castle takes matters into his own hands, reaching out to a shadowy fixer to help him recover Alexis. But Castle soon learns that his daughter's kidnapping may be part of an even more sinister agenda.

When a young woman appears to have literally been scared to death three days after watching a "haunted" DVD, Castle and Beckett delve into one of their creepiest cases yet. To make matters worse, Castle becomes convinced that he too is marked for death when he accidentally watches the cursed video.

When a man is found dead in an industrial cake mixer, Castle and Beckett trace the murder to an Irish gang in Staten Island and a beautiful bar owner named Siobhan O’Doul. Much to everyone’s surprise, Detective Ryan has a complicated history with Siobhan and the Staten Island crime family from his days working undercover in narcotics. When the case hits a dead end, Ryan must go back undercover to expose the killer, complicating his relationship with his wife.

In the show’s 100th episode, Castle finds himself in the unfortunate position of NOT being able to work a case. While he’s holed up in the loft with a broken leg, Beckett goes off to investigate the death of an IRS agent without him, leaving Castle miserable and bored. But when he thinks he witnesses the murder of a young woman in the apartment across the street, he is thrown into a "Rear Window"-esque murder mystery that hits much too close to home.

When Castle and Beckett find giant footprints at the site of a vicious murder, the team is forced to confront the unlikely theory that Bigfoot is the killer. But as they trek into the world of primate research, big game hunting and mythological creatures, they realize that finding the man (or beast) responsible may put them on the endangered species list.

When Beckett is assigned to protect Erik Vaughn, a charming billionaire entrepreneur whose life is in danger, she's forced to reflect on her relationship with Castle which has begun to plateau. Meanwhile, consumed with jealousy, Castle goes to extraordinary lengths to solve the case and separate the two of them.

Beckett's life is on the line when she steps on a pressure sensitive bomb. While the team searches for a way to disarm the explosive, Castle distracts Beckett by arguing with her about who fell for whom first.

When Homeland Security inexplicably seals the crime scene of a car bombing, Castle and Beckett find themselves with two mysteries on their hands: who murdered the victim, a government whistleblower, and why are federal agents trying to take over the case? The plot thickens when they discover that the victim wasn't killed by a car bomb but by a missile from a military drone.

In the season finale, an interview with a high-profile federal law enforcement agency forces Beckett to reconsider what she wants out of her job and out of her relationship with Castle. Meanwhile, the body of a young woman is found floating inside the water tank of a skid row flop house, but as the team investigate, they discover that her final resting place is just one of many strange things about her death.

Last season ended with Beckett wrestling over whether to take a high-profile job in DC -- a dilemma made more complicated when Castle proposed to her. In the Season 6 Premiere of "Castle," Castle and Beckett will deal with the consequences of their decisions against the backdrop of a high-stakes investigation.

Continuing from the season premiere episode, Beckett races against time to find a stolen toxin capable of killing tens of thousands of people. To make matters worse, Castle was exposed, leaving him with less than 24 hours to live.

With Beckett still in D.C., Castle and the boys investigate the murder of former child star Charlie Reynolds, who rose to fame playing the lovable nerd on an early 90s High School sitcom. But the case takes a turn for the strange when Agents Beckett and McCord arrive from Washington to take over the investigation, creating competitive tension in the precinct. But why would a washed-up actor's death warrant Federal scrutiny? Whatever the reason, Beckett and McCord aren't telling. Meanwhile, Castle has to contend with a new face at the 12th, NYPD Detective Frank "Sully" Sullivan.

A desperate young murder suspect, Emma Briggs, takes hostages at gunpoint then mysteriously insists that she will only negotiate with one person: Richard Castle.

A grisly murder investigation leads Castle and Beckett to a suspect who claims he's traveled back in time to stop terrible events from unfolding, events that will change the course of human history. Is he simply a deluded killer, or is it possible that he's telling the truth?

As Castle and Beckett investigate the ritualistic murder of a young woman, they find strange symbols in the victim's apartment; Castle struggles with Alexis' decision to move in with Pi.

Alexis enlists Castle’s help on an Innocence Review case to prove that a death row inmate, Frank Henson, was wrongly convicted. With only 72 hours left before his execution, Castle and Alexis (with help from Beckett) urgently investigate the original murder, only to uncover explosive secrets that may seal Frank’s fate.

When a famed relationship therapist is murdered, it appears that her access to the secrets of her elite and powerful clients led to her death. But when Castle and Beckett discover the victim was in possession of a rare object worth millions of dollars, they realize that this case may be even more complicated – and dangerous – than they thought.

Castle and Beckett arrive at a crime scene to discover that the female victim bears a shocking resemblance to Medical Examiner Lanie Parish. As the team tries to make sense of this mystery, they realize the killer may be targeting detectives of the 12th Precinct. Dr. Kelly Nieman, an exclusive Manhattan cosmetic surgeon who draws Castle and Beckett's interest because of her connection to the victim.

Before dying, he hands a mysterious bundle to the priest. When the bundle turns out to be a smiling baby boy, Castle and Beckett find themselves accidental nannies to the newborn. But when they determine the baby and the victim were not related, they discover that finding his rightful parents may be just as hard as solving the murder.

When Castle and Beckett discover that the victim of a building fire was actually shot to death, they get on the trail of a serial arsonist turned murderer. Meanwhile, Ryan's wife, Jenny, goes into labor, but disaster threatens to ruin the joyous moment.

The murder of a young record store clerk takes a strange turn when the team discovers his past history as a high-level hacker. But it's nothing compared to the shock Castle receives when their investigation leads them straight to his father, Jackson Hunt.

When a pop star is found dead in an alley, Beckett and Castle look into her hard-partying lifestyle; a shocking revelation rocks the investigation.

When the assistant to Modern Fashion Magazine’s dictatorial editor Matilda King is found murdered, Castle and Beckett are thrust into the glitzy, ruthless world of high fashion in their search for the killer. Meanwhile Beckett’s history in the modelling world gets her access to a very special wedding surprise.

The murder of a high school mean girl draws Castle back to one of his many alma maters, where he is giddy to learn that the evidence points to a surprising perpetrator - a teenage telekinetic, throwing he and Beckett into a real-life "Carrie."

When a guilt-ridden young woman confesses to the murder of a struggling actor -- knowing details only the killer could know -- Beckett and Castle seem to have an open-and-shut case, until they uncover proof that their suspect couldn’t possibly be the killer. When a second person confesses, equally convinced they committed the murder, the team realizes the case is far more mysterious than they thought.

Beckett is recruited to assist on a Narcotics investigation, but a routine mission turns deadly when an undercover operation goes array. To survive, Beckett must engage in a battle of wits against some of the most dangerous men in the New York underworld – including a powerful enemy from her past.

When a Japanese ballet dancer is mysteriously murdered, Castle and Beckett's investigation into her secret life uncovers evidence that she was killed by a ninja, and now that ninja is coming after them.

Castle and Beckett investigate the murder of a Wall Street trader, but the case takes a shocking turn when the they discover the victim was an undercover informant for the U.S. Attorney’s office. To complicate matters further, the U.S. attorney involved is Elizabeth Weston, Captain Gates’ estranged sister.

When construction workers find the body of an infamous New York mobster who disappeared in the seventies, Beckett and Castle try to solve this three decade-old mob hit. Unfortunately, their only witness is a man who thinks it’s still the 1970’s, so to uncover what he knows, they must play into his delusion, and party like it’s the last days of disco.

Castle and Beckett delve into the world of extreme sports when a mysterious motorcyclist shoots an up-and-coming professional skateboarder.

A secret investigation conducted by Beckett related to her mother's murder goes awry when a man she has been surveilling is killed. When evidence links Beckett to the victim, she and Castle become the targets of a manhunt that puts both of them in grave danger.

Castle and Beckett's long-awaited wedding is almost here, but when a shocking surprise threatens to ruin the big day, they are sent on a wild mission filled with masked men, angry bikers and a charming ne'er-do-well from Beckett's past.

Beckett is called to an accident scene to find Castle's car in a ravine, engulfed in flames.

While the team investigates the murder of a toy company CEO, Castle uncovers a lead to his mysterious disappearance, launching him into a dangerous investigation of his own.

When a pool shark is murdered by an unseen force, Castle and Becket uncover evidence that the killer may have paranormal powers. Meanwhile, Castle and Beckett attempt to get their lives back to normal following his disappearance.

When an ice cream vender is shot, evidence leads Beckett and Castle to believe that an unknown second-grader may have vital information about the case. Castle goes undercover at an elementary school to try and identify the second-grader but nothing goes as planned.

When a web celebrity is murdered, Castle and Beckett explore the flashy world of internet fame. But when the killer posts pictures from the crime scene on a photo-sharing site, they realize they are up against a social media sociopath who may strike again.

A murder investigation launches Castle into what seems to be an alternate universe where he's never met Kate Beckett. Castle has to convince Beckett, Esposito and Ryan -- now complete strangers -- to let him participate in their investigation so he can find his way back to his own world. This inspires Castle & Beckett to finally take a trip to the altar.

When Castle and Beckett learn that a murder victim may have been poisoned at an Old West-style resort, they visit the resort posing as newlyweds to uncover the truth.

When subway passengers, including Detective Esposito, are taken hostage by a mysterious gunman, Castle, Beckett and the team must uncover the gunman's agenda before it’s too late.

When the star of Castle’s favorite ‘80’s action movie is mysteriously murdered, Castle and Beckett delve into the victim’s secret past and pursue his killer with help from a team of aging action heroes.

When an ER physician is gunned down in the street, Castle and Beckett soon discover that the victim was a mob doctor to a Mafia family run by an old friend of Castle's. Also, against this backdrop of Christmas, Esposito and Lanie reach a defining moment in their relationship.

After being banned from the 12th precinct, Castle works his first case as a private investigator.

When a young actress is murdered, the investigation leads Beckett and Castle into the flamboyant world of a telenovela.

Castle takes on a routine P.I. case, but the investigation turns deadly when he witnesses a murder.

When clues in a murder implicate Castle and Beckett's nemesis, Dr. Kelly Nieman, Castle is called in to consult on the case.

Stakes rise as the 12th Precinct matches wits with serial killers Jerry Tyson (3XK) and Dr. Kelly Nieman. With the clock ticking, Castle and the team must crack the case before the killers claim their next victim.

When an astronaut, training for a trip to Mars, is mysteriously killed inside a Mars simulation, Castle and Beckett don spacesuits to investigate. But when they discover no one inside the sealed simulation could have committed the murder and no one from the outside could get in, the case takes a shocking turn

After a man is mysteriously murdered in a park, Castle and Beckett team up with a competitive, high-powered female detective from Hong Kong, who has information about the victim. But as Beckett digs deeper into the case, she realizes neither her Hong Kong colleague nor the victim may be quite who they seem.

Detective Kevin Ryan is on the security detail of a charismatic congressman attending a charity event when shots suddenly ring out. Driven to apprehend the killer, Ryan must revisit the events that led up to the shooting, with the help of Castle and Beckett.

When Richie “The Pitbull” Falco, a larger-than-life personal-injury attorney is found dead, Beckett and Castle investigate the many clients and competitors who had motive to kill him. But the mystery deepens when they discover a shocking secret that may be linked to Richie’s murder.

A mysterious recurring dream drives Castle and Beckett to seek answers about the two-month period when he went missing. But their search for the truth has deadly consequences.

As Castle and Alexis travel to London, their routine flight turns deadly when the plane’s Air Marshal is found murdered. With the help of Beckett on the ground, Castle and Alexis race against time to find the killer before he carries out his fateful plan.

When Sid Ross, the powerful creator of a long-running sketch comedy show is killed, Castle and Beckett are called to investigate. But as they delve into the victim’s life and the colorful world of “Saturday Night Tonight,” they uncover a shocking secret that may explain Sid’s murder.

A death in the woods draws Castle back to a terrifying and defining event in his childhood. Investigation leads to obsession, as he attempts to unearth answers that have eluded him for decades, all while Beckett faces a crossroads of her own.