A beloved former major league baseball player is found dead after a goodwill trip to Cuba. The investigation, which includes running into Joe Torre, leads the detectives into New York’s Cuban community to solve the murder. Meanwhile, Alexis’ genealogy project forces Castle to consider the identity of his unknown father.

Castle and Beckett investigate the death of an Irish mobster, but while on the case they uncover what may be an international drug smuggling operation, as well as the killer may be involved in the murder of Beckett’s mother.

Castle and Beckett are called to a wedding to investigate the murder of a bridesmaid. Castle realizes that the wedding is from a former girlfriend Kyra. Everyone’s feelings are compromised, since Kyra has doubts about who she is marrying, Castle’s feelings may not be as objective in the case and Beckett picks up the connection between them, making her a little jealous and have poor judgement.

Castle and Beckett investigate an art dealer that is shot in his gallery, but the bullet is inexplicably missing from the crime scene. To add to that, the only witness suffers from amnesia.

A man’s body is discovered in an apartment building’s garbage chute, and two women surface to identify the deceased—his wife and his fiancée. Castle and Beckett’s investigation uncovers the man’s complex double life. DB Woodside guest stars

The murder of an Assistant District Attorney thrusts Castle and Beckett into the world of ex-cons and escorts. But when Castle’s desire to help a vulnerable call girl endangers the case, Beckett is forced to decide between honoring promises and putting a killer behind bars. Matters are complicated even further when Castle’s daughter shares a potentially explosive secret with Beckett instead of her father

After a bike messenger, carrying a package with content that is able to free a wrongly convicted man from pison, is brutally murdered, Castle and Beckett need to investigate the case. But they are surprised to find out that the tragic death is linked to another murder case previously investigated by Captain Montgomery. Now, in order to solve the new murder, Castle and Beckett must dig deep and discover all the secrets of a prominent New York family.

When an up-and-coming rock star’s dead body is found staged in a scene straight out of her hit music video, Castle and Beckett delve into the world of obsessed fans, sleazy managers and jealous band members.

As Halloween approaches, Castle and Beckett are called to a graveyard where the body of a young man sporting vampire fangs has been discovered with a wooden stake driven through his heart.

Castle has a new book agent, Paula Haas, but she talks with him when he has gotten an opportunity that may change his career. The downside is that taking the opportunity would mean the end of his relationship with Beckett.

The mysterious circumstances surrounding an Arctic explorer’s death take Castle and Beckett to the halls of the CIA; Castle believes the killer may be fooling the investigators.