
With tensions rising between Castle and Beckett, Castle finds himself a new partner — Detective Ethan Slaughter (guest star Adam Baldwin, “Firefly”), a tough and colorful cop from the city’s gang unit. But Castle gets more than he bargained for when Slaughter shows him a grittier side of police work that puts Castle in the line of fire like never before.
Air date: April 6, 2012 / Directed by John Terlesky / Written by Alexi Hawley
Guest Cast: Adam Baldwin as Detective Ethan Slaughter, Michael McGrady as Brian Reilly, Michael Dorn as Dr. Carter Burke.