Mark Harmon returns as Gibbs in 'NCIS: Origins' Season 3

Mark Harmon will reprise his role as Leroy Jethro Gibbs in a season-long arc throughout Season 3 of CBS prequel series "NCIS: Origins," appearing in every episode. The casting was confirmed by CBS and reported by Variety. Harmon originally made Gibbs iconic in the long-running parent series "NCIS."