NCIS (Naval Criminal Investigative Service) is a media franchise of American television programs originally created by Donald P. Bellisario and currently broadcast on CBS, all of which deal with military related criminal investigations based on the Naval Criminal Investigative Service of the United States Department of the Navy, which includes the United States Navy and the United States Marine Corps. In 2003, NCIS was introduced via a backdoor pilot, from the TV show JAG with NCIS in turn spinning off NCIS: Los Angeles, NCIS: New Orleans, and NCIS: Hawaiʻi in 2009, 2014, and 2021 respectively. NCIS: Los Angeles had a proposed spin-off, but it was not picked up by CBS. Four television series make up the bulk of the NCIS franchise: NCIS, Los Angeles, New Orleans, and Hawaiʻi. All series in total amount to 954 episodes across 43 seasons of television. The main NCIS series is the longest-running show of the franchise, which premiered its twentieth season on September 19, 2022.