Mark Harmon NCIS Special Agent Leroy Jethro Gibbs Actor Sasha Alexander NCIS Special Agent Caitlin Todd Actor Michael Weatherly NCIS Special Agent Anthony "Tony" Dinozzo Actor Pauley Perrette Forensic Specialist Abby Sciuto Actor Sean Murray NCIS Special Agent Timothy McGee Actor David McCallum Dr. Donald "Ducky" Mallard Actor Brian Dietzen Jimmy Palmer Guest Star Joe Spano Senior FBI Agent T.C. Fornell Guest Star Hilary Salvatore Petty Officer Jessica Smith Guest Star Dean McDermott Lt. Cmdr. Allan Witten Guest Star Brigid Brannagh Catherine Reynolds Guest Star Dan Ziskie Capt. Ross Vetter Guest Star Molly Hagan Audrey Vetter Guest Star Jennifer Dundas Lynn Simons Guest Star Robert Manning Jr. Officer Alex Taylor Guest Star Jonathan Redford Corpsman Timothy Morgan Guest Star Kevin Quigley William the Truthteller Guest Star Donald P. Bellisario Executive Producer Jeff Woolnough Director Frank Military Writer