NCIS paved the way for numerous spinoffs since its 2003 premiere - including the prequel series, NCIS: Origins, which fans will notice features more than one familiar character. When NCIS began, it followed Special Agent Leroy Jethro Gibbs, played by Mark Harmon, and his team of naval investigators stationed in Washington, D.C. More than 20 years later, CBS created NCIS: Origins, which shows how Gibbs, now played by Austin Stowell, got started as a naval investigator in 1991.