NCIS has been a monumental series that has run for over fifteen years. For nearly twenty seasons, NCIS has captivated fans with compelling stories, exciting action, and wonderful characters. The story of the Naval Criminal Investigation Service has produced some of the most heartwarming characters, such as the dedicated Timothy McGee, the charismatic Anthony Dinozo, the amazing Ziva David, and of course, the sphinxlike Jethro Gibbs.