The first season of the American police procedural drama NCIS was originally broadcast between September 23, 2003, and May 25, 2004, on CBS.
The first season dealt with introducing the characters and their strengths, skills, and weaknesses. Three recurring characters are also introduced: the main foe for the first two seasons, Ari Haswari; Special Agent Timothy McGee and Jimmy Palmer who replaces Gerald Jackson, Ducky's assistant, after he was shot. The season also introduces Sasha Alexander as Special Agent Caitlin Todd who serves as Special Agent Vivian Blackadder's (Robyn Lively) replacement, who was a member of Gibbs' team during the two-part JAG backdoor pilot.