Mark Harmon NCIS Special Agent Leroy Jethro Gibbs Actor, Executive Producer Sean Murray NCIS Special Agent Timothy McGee Actor Emily Wickersham NCIS Special Agent Eleanor "Ellie" Bishop Actor Wilmer Valderrama NCIS Special Agent Nicholas "Nick" Torres Actor Maria Bello Special Agent Jacqueline "Jack" Sloane Actor Brian Dietzen Dr. Jimmy Palmer Actor Diona Reasonover Forensic Scientist Kasie Hines Actor Rocky Carroll NCIS Director Leon Vance Actor, Director David McCallum Dr. Donald "Ducky" Mallard Actor Dabney Coleman Army Corporal John Sydney Guest Star Luke Edwards Tommy Mulligan Guest Star Johnny Wactor Navy Lieutenant Ross Johnson Guest Star Sam Littlefield Oliver Sherry Guest Star Daniel E. Smith Cal Frazier Guest Star Rochelle Robinson Megan Boone Guest Star Ian Duncan Michael Deegan Guest Star Lisa Maley NCIS Probationary Agent Anna Ventura Guest Star Jess Allen Burly Bodyguard Guest Star Adam Aguirre Uniformed Room-Service Guy Guest Star Chas. Floyd Johnson Executive Producer Mark Horowitz Executive Producer Frank Cardea Executive Producer George Schenck Executive Producer Steven D. Binder Executive Producer Scott Williams Executive Producer Donald P. Bellisario Executive Producer Brendan Fehily Writer