Logline: As Castle and Alexis travel to London, their routine flight turns deadly when the plane’s Air Marshal is found murdered. With the help of Beckett on the ground, Castle and Alexis race against time to find the killer before he carries out his fateful plan.
Original airdate: April 27, 2015
Filming dates: March 16 to March 25
Written by: Dara Creasey
Directed by: Bill Roe
Guest cast: Paula Newsome as Debbie Parker, Inbar Lavi as Farrah Darwaza, Josh Dean as Jim Kogut, Nick Greene as Aiman Haddad.