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 David McCallum Dr. Donald "Ducky" Mallard Actor Jason Gerhardt Marine Colonel Jonah Park Guest Star Shea Buckner Xavier Blackburn Guest Star Rif Hutton Marine General Phillip Braxton Guest Star Joe Nieves Justin Kinneman Guest Star JT Neal Dean Guest Star Taylor Blackwell Trista Guest Star Alex Ball Navy Senior Chief Richard Granger Guest Star Cybus Bobak Aazar Atwa 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 Jennifer Corbett Writer Thomas J. Wright Director