Mark Harmon and Michael Weatherly Reunite on Screen After a Decade

Mark Harmon and Michael Weatherly share the frame again on Tuesday, Oct. 20, in a new episode of "NCIS: Origins" — their first on-screen reunion as Gibbs and DiNozzo in a decade. The moment arrives only in brief present-day scenes at the beginning and end of the hour, but for a franchise now 23 years old, it lands as an event.

Showrunner David North, who wrote for the characters on the original "NCIS," told Variety the reunion was long a fan's hope before it became a producer's plan. "As just a fan of the franchise, it was something I'd always hoped would happen," he said. "But to be honest, I didn't really ever foresee it happening in 'Origins,' until after season 2, when I really started coming up with this idea of a story that would happen in present-day."

How the reunion came together

North pitched a present-day story to Harmon after season 2, and Harmon agreed. Weatherly followed. On set, North said, the two actors slipped back into rhythm instantly. "They both hit the ground running. You wouldn't have thought there was 10 years in between," he said. "We kind of just were watching and admiring them and thinking of what they had accomplished together."

In the story, Weatherly's DiNozzo now serves as director of the agency, while Harmon's Gibbs remains retired in Alaska but works a case of his own across the season. Their catch-up scene plays to type: DiNozzo talks, Gibbs does not. North noted DiNozzo has much to recount from the Paramount+ series "Tony and Ziva," while Gibbs "really has been kicking back in Alaska."

What does the reunion change for the season?

The structure holds. Roughly what viewers saw in the first three weeks — mostly the 1993 storyline with close-ended cases — will define the season, North said. But the serialized 1993 story "is directly informing what's happening with Mark in present-day," and the past "has come back to haunt him in the present."

Harmon's return grew from his seasons of off-screen involvement as executive producer and narrator. "When I walk on the set with him, you just see the respect and the love that everyone has for him," North said.

The episode also features substantial young Ducky, played by Adam Campbell — a choice North made deliberately, expecting new viewers to tune in. The late David McCallum "loved Adam and thought the world of him," North said. A present-day beat finds Gibbs wishing he had reconnected with Ducky before his death. "Gibbs does miss Ducky just the same as Mark misses David," North said.

The Lala question

On young Gibbs's romance with Special Agent Lala Dominguez (Mariel Molino), North promised speed over cliché. "We're going all in. Things are gonna progress fast, for better or worse," he said, adding that no Reddit thread has yet predicted the ending: "I haven't had anyone predict what's actually gonna happen yet."

More crossovers are coming. Emily Wickersham will reprise Ellie Bishop in several episodes starting Oct. 27. North quoted Harmon calling this the season of "grip it and rip it." "We're not holding anything back," he said. "It was a special day in my life, honestly, to see that happen after a decade."