Mark Harmon Is Making a Full-Time Return to the ‘NCIS’ Universe For an Entire Season

Mark Harmon will make a full-time return to the ‘NCIS’-verse, reprising his role as Leroy Jethro Gibbs in the 2026-27 season.

Mark Harmon will be returning full-time in the role of Leroy Jethro Gibbs that he created on NCIS, in a season-long arc of the upcoming third season of prequel series NCIS: Origins.

CBS today posted on Instagram, “the story he never told enters a new chapter… Mark Harmon will return to NCIS: Origins as Gibbs for all episodes of Season 3. 👏👏 #NCISOrigins #NCIS #MarkHarmon #Gibbs”

He will take part in a “present-day mystery tied to his ‘90s Camp Pendleton days in an action-packed story that unfolds all season long.”

Harmon currently narrates NCIS: Origins as well as serves as an executive producer on the series. Season 3 of NCIS: Origins has been reduced to 10 episodes but Harmon is going to appear in each and every one in “the next chapter in the iconic character’s story.”

Harmon most recently appeared on NCIS: Origins in November 2025 during the crossover event with the mothership, and it was revealed that Gibbs was still living in Alaska, but had been joined by a canine roommate. He also appeared briefly in the series premiere.

Harmon originated the character of Gibbs in the NCIS backdoor pilot that aired as two April 2003 episodes of JAG. He continued as Gibbs until his exit in episode four of NCIS Season 19.

Austin Stowell stars as a young Gibbs in NCIS: Origins during his early days at Camp Pendleton. The cast also includes Kyle Schmid, Mariel Molino, Tyla Abercrumbie, Diany Rodriguez and Caleb Foote.

The third season of NCIS: Origins will premiere this fall in its new timeslot, Tuesday nights at 10 p.m. ET/PT.