NCIS season 1

The 1st 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.

Main

 * Mark Harmon as Leroy Jethro Gibbs, NCIS Supervisory Special Agent (SSA) of the Major Case Response Team (MCRT) assigned to Washington's Navy Yard
 * Sasha Alexander as Caitlin Todd, NCIS Special Agent and former Secret Service Special Agent assigned to the security detail of the President of the United States
 * Michael Weatherly as Anthony DiNozzo, NCIS Senior Special Agent, second in command of MCRT
 * Pauley Perrette as Abby Sciuto, Forensic Specialist for NCIS
 * David McCallum as Dr. Donald "Ducky" Mallard, Chief Medical Examiner for NCIS

Recurring

 * Alan Dale as Thomas Morrow, NCIS Director
 * Alicia Coppola as Faith Coleman, JAG Commander
 * Joe Spano as Tobias Fornell, FBI Senior Special Agent
 * Pancho Demmings as Gerald Jackson, Assistant Medical Examiner for NCIS and Ducky's first assistant
 * Patrick Labyorteaux as Bud Roberts, JAG Lieutenant from Falls Church
 * Joel Gretsch as Stan Burley, NCIS Special Agent Afloat on the USS Enterprise (CVN-65) and former member of Gibbs' team
 * Kent Shocknek as Guy Ross, ZNN news anchor
 * Sean Murray as Timothy McGee, NCIS Probationary Special Agent who works at the Norfolk Naval Base
 * Jessica Steen as Paula Cassidy, NCIS Senior Special Agent assigned to Guantanamo (GTMO or Gitmo) Bay Detention Camp in Cuba
 * Tim Kelleher as Chris Pacci, NCIS Special Agent
 * Rudolf Martin as Ari Haswari, rogue Mossad Agent
 * Brian Dietzen as Jimmy Palmer, Assistant Medical Examiner for NCIS and temporary replacement for Gerald after he gets shot

Guest appearances

 * Adam Baldwin as Michael Rainer, Navy Commander
 * Eric Ladin as P.O. Thompson