Headhunters

Summary

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

Guest stars

• Adam Baldwin as Ethan Slaughter
• Michael McGrady as Brian Reilly
• Reynaldo Gallegos as Cesar Vales
• Anna Zielinski as Laura Wilson
• Clifford McGhee as Maxi
• Mario Ardila, Jr. as Gilberto Mendoza
• Miles Tagtmeyer as Glitch
• Michael Dorn as Carter Burke
• Jan M. Janssen as Officer Jenkins