Mark Harmon Returns to ‘NCIS’ With an Emotional Callback to Gibbs’ Early Days

Mark Harmon returned as Leroy Jethro Gibbs during the Nov. 11 NCIS/NCIS: Origins crossover – his first on-screen appearance as the character since leaving NCIS in 2021 (aside from a brief cameo in the prequel’s 2024 debut).

Harmon, 74, opened the Origins episode “Funny How Time Slips Away” as an older Gibbs reflecting on “three decades” in the job. While pouring a drink, he recalled his early career before turning his attention to a stray dog he’d taken in ahead of an approaching storm. Gibbs noted he once worked with a dog “that had a first and last name – Special Agent Gary Callahan,” adding that he’d been lucky to work with “a lot of good guys.”

As Willie Nelson’s song played, Gibbs looked over old photos – then seamlessly de-aged into Austin Stowell’s younger Gibbs to launch the 1990s storyline. The crossover continued in NCIS with the episode “Now and Then.” The ending also mirrored this transition by aging Kyle Schmid’s Mike Franks into Muse Watson’s older version from NCIS.

Though largely absent on screen in recent years, Harmon remains an executive producer and narrates every Origins episode. Showrunners previously teased that Gibbs was “no longer alone” after his Alaska departure – and his new K-9 companion confirms it.

Harmon told The Wrap that revisiting Gibbs’ life today was “interesting,” and that the short scene “made me smile.” He added that fans will learn things about Gibbs “they don’t know already.”