<P> 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 . </P>
<P> 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 . </P>
when did the first episode of ncis air
when did the first episode of ncis air
September 23 , 2003
September 23 , 2003