Castle & Beckett work a murder case around the theft of a valuable sculpture. Kristin Lehman guest stars as Serena Kaye, a smart, sexy insurance investigator, who joins Castle & Beckett in the investigation, but she also has her eyes set on Castle, all the while hiding a very important secret from the team. Jessica Tuck also guest stars as Joy McHugh, a wealthy museum benefactor who becomes a suspect in the murder investigation.