Is Mark Harmon Returning to 'NCIS'? What We Know So Far 4 Years After His Exit

Will NCIS fans see Special Agent Leroy Jethro Gibbs again?

Four years after Mark Harmon left the hit series, CBS confirmed he will return during the first crossover event between NCIS and NCIS: Origins on November 11. The Veterans Day crossover will focus on Austin Stowell's younger Gibbs and his team as they investigate a naval officer's death in the 1990s, according to Deadline.

"I'm very proud of the storytelling that David [J. North] and Gina [Lucita Monreal] are doing on Origins," Harmon said in a statement. "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."

"Four years ago, Gibbs disappeared to Alaska to live a life of solitude," North and Monreal shared, adding, "We don't want to give too much away, but let's just say Gibbs is no longer alone."

After 18 years on NCIS, Harmon made his final appearance on the long-running procedural in the fourth episode of Season 19 in 2021.

Showrunner and executive producer Steven D. Binder said Harmon would continue "to be an integral part of the fabric of the show" as an executive producer. He also hinted at the character's potential return in the future.

"Our north star has always been staying true to our characters, and that truth has always guided the stories we tell and where those characters go," he added. "So regarding the future of Gibbs, as long-time fans of the show may have noticed over the years … never count Leroy Jethro Gibbs out."

Long before CBS confirmed Harmon's NCIS return, OK! learned the 74-year-old actor was eyeing to come back to the hit show.

"Mark's been teasing a return to the show and everyone wanted him back," an insider told Star. "He's still on the fence when it comes to going back to the grind. People wish he would stop getting them excited only to let them down."

On the other hand, the source claimed Wilmer Valderrama was not thrilled about the plan as he would prefer Harmon to continue his executive producing duties instead.

"Wilmer has nothing personal against Mark, but he wouldn't mind if he never came back," said the source. "This has been Wilmer's time to shine and he feels like he's finally a main star, not a supporting player."

Two years after he left the show, Harmon revealed the surprising reason he took the NCIS role.

"The name Leroy Jethro Gibbs hit me," he said in a 2023 interview. "And there was a moment there where in that couple of days I think it changed to Bob Robinson or something. … And I right away called up and said, 'The name has got to change back.' And then someone said, 'You can't play a guy named Leroy Jethro Gibbs.' I said, 'Why not?'"

He admitted, "If that name had not been there, I don't think I would have been there."