Mark Harmon is reprising his NCIS role as Leroy Jethro Gibbs, and we don’t mean as just a voice on NCIS: Origins. The actor will appear during the first-ever crossover event between the two CBS shows, but rather than returning on NCIS, Harmon’s special guest spot will happen on the prequel series NCIS: Origins, which Harmon narrates and executive-produces. It will be the first time Harmon has stepped back into Gibbs’ shoes since he made a brief cameo in the NCIS: Origins pilot in 2024.
The two-part crossover kicks off with Origins on Veterans Day, Tuesday, Nov. 11, at 8/7c, as “younger Gibbs (played by Austin Stowell) and team investigate the small-town death of a naval officer in the ’90s,” reads the official synopsis. The case is then “unexpectedly re-opened in the present day” on NCIS at 9 pm. Get a first look below at Gibbs’ return, which will reveal how — and with whom! — the character has been spending his time.

“Four years ago, Gibbs disappeared to Alaska to live a life of solitude,” the spinoff’s showrunners David J. North and Gina Lucita Monreal said in a statement. “We know how much fans have missed seeing Mark and have wondered what Gibbs is up to today. Well, on Nov. 11, we’re so excited to announce that Mark Harmon will return as Leroy Jethro Gibbs in the Origins hour of the NCIS crossover event. We don’t want to give too much away, but let’s just say Gibbs is no longer alone.”
Added Harmon: “I’m very proud of the storytelling that David and Gina are doing on Origins. They continue to push boundaries and dive deeper into the characters’ backstories. They came to me with an idea for Gibbs that I liked, and it seemed like a good time to check in with him. I hope fans enjoy it.”