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 invol... (more)ved is Elizabeth Weston, Captain Gates' estranged sister.

Juan Carlos Cantu, Kevin Kilner, Laurie Fortier, Ramon Fernandez, Rosie Garcia, Salli Richardson-Whitfield