NCIS: How Many Episodes Was Mark Harmon's Gibbs In?

Mark Harmon and "NCIS" are inextricably linked to one another. As its lead, Harmon was the face of "NCIS" for the majority of its ongoing run, and given its length at the time of his departure, he portrayed Leroy Jethro Gibbs for far longer than almost any other actor has stuck with a single character outside the world of soap operas.

Overall, Harmon plays Gibbs in 435 episodes of "NCIS." His total number of appearances as the character is technically even higher — after all, "NCIS" is a spin-off of "JAG," and Harmon debuts as Gibbs in two episodes of "JAG" that predate the start of "NCIS." He also shows up in four episodes of "NCIS: New Orleans," raising the number of canonical Gibbs appearances to 441. Harmon even voices Gibbs in a fictional "NCIS" broadcast that airs in an episode of "Family Guy," arguably increasing the Gibbs counter by one additional episode.

Harmon's final appearance as Gibbs is in "NCIS" Season 19, Episode 4. That said, he isn't done with the show entirely. Past his Season 19 exit and continuing through Season 20, Harmon is credited as a producer, extending his influence on the hit procedural beyond his impressive 435-episode run.

While Mark Harmon is no longer a part of the main "NCIS" cast, the probability of his return at some point in the show's future is high. In conjunction with his final episode premiering on CBS, Entertainment Tonight interviewed showrunner Steven D. Binder about Harmon's exit. Binder was quick to leave the door open for the seasoned actor to reprise his iconic role. "Regarding the future of Gibbs, as longtime fans of the show may have noticed over the years... never count Leroy Jethro Gibbs out," he said.

One anonymous source claiming to know Harmon even told Closer Weekly that he was planning on an "NCIS" return before deciding to devote his time instead to writing "Ghosts of Honolulu," a non-fiction book about espionage in World War II. "Mark's been teasing a return to the show and everyone wanted him back," they said. "He's still on the fence when it comes to going back to the grind."

Both the producers of "NCIS" and Harmon himself seem to be plenty interested in future Gibbs appearances. The biggest question about the character's future, then, isn't if, but when his return might manifest.