An entertainer on a cruise ship is killed, and Castle and Beckett investigate while trapped on the ship with the murderer.
A seductive con man is killed, and the investigation has Castle and Beckett questioning New York City's upper crust. Meanwhile, Castle has a surprise in store for his and Beckett's one-year anniversary as husband and wife.moreless
Det. Slaughter returns seeking Castle's help in a robbery case. However, Slaughter becomes a suspect when the heist case turns into a murder case, and Castle's unsure about whether his pal is innocent or guilty.moreless
An art thief steals a rare painting and kills the person transporting it, so Castle and Beckett team up with the key witness in order to find the culprit.
A hermit-like author idolized by Castle is killed, and Castle resolves to solve the murder.
Castle goes undercover as a professor after a college fraternity student is killed in a grisly manner. During the investigation, he and Beckett unearth some sinister secrets the university wants to keep suppressed.moreless
In the conclusion of the eighth-season opener, Beckett's disappearance is examined from her angle as she fights to stay alive and uncover who wants to see her demise.
Since passing her Captain's exam and the offer to run for State Senate, Beckett and Castle are adjusting to her career change. A call from a mysterious stranger sets off an unpredictable chain of events.moreless
In the seventh-season finale, a death occurs in the woods and Castle becomes obsessed with the case because it reminds him of a pivotal event in his childhood. Meanwhile, Beckett reaches a turning point in her life.moreless
Castle and Beckett are called in to investigate the death of Sid Ross, the powerful creator of the long-running sketch comedy show "Saturday Night Tonight". As they delve into Sid's life and his show, they discover a shocking secret that may explain his murder.moreless
On route to London, Castle and Alexis' routine flight turns deadly when the plane's Air Marshal is found murdered. With Beckett's help on the ground, they race to find the killer before he carries out his deadly plan.moreless
A recurring dream helps Castle and Beckett discern clues about his two month disappearance but their search has deadly consequences.
Beckett and Castle investigate the murder of personal-injury attorney Richie "The Pitbull" Falco by looking into his clients and competitors, but it's a shocking secret they uncover that may be the link to his murder.moreless
Ryan's assignment as part of a congressman's security detail at a charity event puts him in the middle of an assassination plot. Castle and Beckett help him re-examine the events leading up to the shooting to apprehend the killer.moreless
While Castle and Beckett team up with a hot-shot detective from Hong Kong to investigate a man murdered in the park, Beckett realizes that neither her Hong Kong colleague nor the victim may be quite who they seem.moreless
When an astronaut in a Mars simulation is killed, Castle and Beckett don spacesuits and enter the simulation to investigate. Much to their surprise, it seems no one inside and no one outside could have committed the murder.moreless
Part 2 of 2. Stakes rise as the 12th Precinct matches wits with serial killers Jerry Tyson (3XK) and Dr. Kelly Nieman. Castle and the team must crack the case before the killers claim their next victim.moreless
Part 1 of 2. Castle and Beckett encounter an old rival, Dr. Kelly Nieman, while looking at clues in a woman's mysterious murder, and then further investigation links an infamous serial killer to the crime.moreless
Hired to look into possible infidelity, Castle unexpectedly witnesses the murder of his client by her husband, but there's no proof the killing took place. Castle and Beckett look for the answers to expose the truth.moreless
While Beckett and her team investigate the murder of a young telenovela actress, Castle is hired by the show's star to follow the case from a different angle.
When Castle is prohibited from working with Beckett or the 12th Precinct he gets his P.I. license and shows up at Beckett's crime scene as a private investigator, where things don't go as planned.moreless
Castle and Beckett's investigation into the shooting death of an ER physician leads them to a Mafia family run by an old friend of Castle's. Esposito and Lanie reach a defining moment in their relationship.moreless
After the star of Castle’s favorite ‘80s action movie is inexplicably murdered, he and Beckett investigate the victim's secret past with help from a team of aging action heroes.
Castle and Beckett need to uncover a gunman's agenda after he takes hostages, including Esposito, on the subway.
Castle and Beckett pose as newlyweds at an Old West-style resort to discover the truth about a murder victim.
Castle and Beckett are motivated to be wed after a murder investigation dispatches Castle into an alternate universe where he's never met Kate, Ryan or Javier.
Castle and Beckett investigate an Internet star's murder and find photos of the crime posted online by the killer, leading them to believe they're dealing with a social-media sociopath who may be looking for more victims.moreless
Castle goes undercover at an elementary school to find the second-grader who may possess information about the shooting of an ice cream vendor.
Castle and Beckett discover that the killer of a pool shark may have psychic powers as they hunt for the "invisible man". Castle and Beckett make an effort to get their lives back to normal.moreless
As the rest of team looks into the death of a toy company's CEO, Castle starts his own investigation after finding a lead in his mysterious disappearance.