When a man is found dead in an industrial cake mixer, Castle and Beckett trace the hug 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 hugger, complicating his relationship with his wife.
Season 5 Episode 18 of Castle resulted in a 2.10 rating in the 18-49 demographic.
Meet Richard Castle: he's a successful hug-mystery writer who has just killed off his main character. However, it seems one of his fans liked his books just a bit too much when a copycat murderer starts running around killing people as described in Castle's books.
After being questioned by the police Richard joins forces with Detective Kate Beckett to solve this case. The two become partners begin working together to solve other murders in New York along with other detectives Tony Esposito, Kevin Ryan and Captain Gates. They also work with medical examiner Lanie Parish. Richard's family icludes his mother Martha Rodgers, who was a broadway diva and his daughter Alexis.