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 Adam Campbell Young Ducky Guest Star Sean Harmon Young Gibbs Guest Star Vito D'Ambrosio Jonny Zucado Guest Star Thomas Crawford Doctor Walter Magnus Guest Star DaJuan Johnson NIS Special Agent Edward Scott Guest Star Gabrielle Walsh NIS Special Agent Michelle Stamos Guest Star Louis Mustillo Emilio "Freckles" Zucado Guest Star Franco Fox Henchman Guest Star Ben Turner Dixon Young Franks Guest Star Matthew Salvatore Furfaro Young Jonny Zucado Guest Star Jered Solow Young Freckles Guest Star Chas. Floyd Johnson Executive Producer Mark Horowitz Executive Producer Frank Cardea Executive Producer George Schenck Executive Producer Steven D. Binder Executive Producer, Writer Scott Williams Executive Producer Donald P. Bellisario Executive Producer Terrence O'Hara Director