Deadline reported that actor Mark Harmon (Freakier Friday, Joey Dakota), known for his 18-season run on CBS’s NCIS as Special Agent Leroy Jethro Gibbs, will be returning to NCIS: Origins as the iconic character in all episodes of the series’ upcoming third season. While Harmon is involved with the prequel spinoff as its executive producer and narrator, and has appeared physically twice prior, this will be the first time his character is a part of the entire story arc.
View the announcement below, via the franchise’s Instagram.
NCIS: Origins precedes the flagship NCIS series by several years – Taking place in the early ‘90s, the storyline follows Austin Stowell (Bridge of Spies, The Hating Game) as a young Leroy Jethro Gibbs in the beginning of his career as a probationary NIS agent post-discharge from the military. Under the guidance of leader and Special Agent Mike Franks (Kyle Schmid; The Covenant, Big Sky), Gibbs joins the ragtag NIS Camp Pendleton Office and its team while navigating the traumatic aftermath of his wife and daughter’s murders.
The series has two seasons under its belt, and was renewed for a third in January 2026. Per Deadline, Harmon appeared prior in the series premiere, and in the second season during a Veterans Day crossover between NCIS and Origins. Now, it’s alleged that he will appear for season three’s entirety as part of a present-day mystery related to his ‘90s Camp Pendleton days.
As listed by Deadline, the series also stars Tyla Abercrumbie (The Chi, Shrink) as Field Operation Support Office Mary Jo Hayes, Caleb Foote (The Kids Are Alright, Made for Love) as Special Agent Bernard “Randy” Randolph, Mariel Molino (Narcos: Mexico, The Watchful Eye) as Special Agent Cecilia “Lala” Dominguez, and Diany Rodriguez (The Blacklist, The Valet) as Special Agent Vera Strickland. Season three’s executive producers, after the departure of co-creator and showrunner Gina Lucita Montreal (Paradise, Seeing Butter) from the series after season two, are credited as David J. North (Rizzoli & Isles, Scorpion), Eric Christian Olsen (NCIS: Los Angeles, Matlock), with Mark Harmon and Sean Harmon (Breakwater, The Downside of Bliss).
The third season of NCIS: Origins is set to air Tuesdays at 10 p.m. ET/PT on CBS in the fall, reports Deadline.