Harmon’s on-screen return is brought on by a case, as the younger Gibbs (Austin Stowell) investigated it in the early 1990s. The same case, about the death of a naval officer, is reopened by Gibbs’ former co-workers in NCIS season 23. It serves as an opportunity for the franchise to examine some of the rules that Gibbs has lived by, although Harmon doesn’t remember all of them.
In an interview with Entertainment Weekly, along with fellow NCIS: Origins co-creator Gina Lucita Monreal, North shares a story about having to record a voiceover for some of Gibbs’ famous rules that have recurred throughout the history of NCIS. Harmon, who was the franchise’s lead for most of its run, in addition to being an executive producer on the NCIS: Origins prequel, reveals he doesn’t know the rules — except for perhaps one:
David J. North: We were in the sound studio doing Mark’s voiceover with him the other day. I was talking to him about what this is in episode 5, how so much of it is based on rule No. 11, ‘When the job’s over, walk away.’ And he said, ‘Man, the fans walk up to me nonstop and ask me about those rules.’ I said, ‘Do you know any of them? Do you know one of the rules?’ And he goes, ‘There’s one about a knife.’
Harmon’s appearance in the November 11 episode of the prequel, which puts him alongside the NCIS: Origins cast, is the actor’s first significant on-screen appearance since his 2021 departure, though he did make a quick cameo for the NCIS: Origins season 1 premiere in 2021. As for whether the veteran will return to the main NCIS series, the actor hasn’t completely ruled out the possibility.
Although he’s downplayed a full-time return to the franchise, there could be another instance in which Gibbs will need to appear on-camera. There is still plenty of mystery in terms of how the younger Gibbs gives way to the version that audiences know and love in NCIS, so it’s possible that Harmon could get another chance at learning the many rules of his most recognizable portrayal.
