As the NCIS franchise prepares for the full-time on-screen return of Mark Harmon this October, showrunner David North has revealed that one of the series’ most pivotal moments—the departure of Leroy Jethro Gibbs—was written with surprising speed.
Speaking on the Partners & Probies podcast in September 2026, North detailed the writing process behind the Season 19 episode “Great Wide Open.” He noted that the final sequence in Alaska, where Gibbs finds peace while fishing in a remote river, took approximately 10 minutes to write. North co-wrote the 2021 episode with Brendan Fehily, and while other portions of the script underwent standard revisions, the dialogue for Gibbs’ farewell to Timothy McGee was penned almost immediately.
The efficiency of that 2021 exit contrasts with the long-term planning currently surrounding Harmon’s return to the universe. Mark Harmon is confirmed to appear on-screen in every episode of NCIS: Origins Season 3, which is scheduled to premiere on October 6, 2026. While Harmon has been involved in the prequel series as an executive producer and narrator, the upcoming season marks his most significant physical presence in the franchise since the Alaska sequence.
The new season of NCIS: Origins will also feature a casting shift for the Harmon family. Sean Harmon, who has frequently portrayed a younger version of his father’s character in flashback sequences, will join the Season 3 cast in a different capacity. Rather than playing a young Gibbs, he is set to guest star as a new character, FBI Agent Casey Bloom.
These developments come as the production navigates a change in leadership. Gina Lucita Monreal departed her role as co-showrunner of the prequel series following the Season 2 finale. The transition occurs just as the franchise expands further with the launch of NCIS: New York, maintaining the heavy production schedule that has defined the brand as Harmon returns to the center of the narrative.
