Mark Harmon exits NCIS after 18 seasons as lead actor

Mark Harmon left the TV drama NCIS in 2021 after playing the same character for 18 years. His character, Leroy Jethro Gibbs, chose to stay in Alaska at the end of a case instead of going back to Washington, D.C. Harmon said he wanted new challenges and found the show's schedule very demanding. He left in episode four of season 19, earlier than many fans expected. Because the character did not officially retire, the show left open the possibility of his return. Harmon also stayed on as an executive producer. In October 2024, he came back to the role as a narrator on NCIS: Origins and took part in a crossover special.