'NCIS' Renewed for Season 21, Staying Strong After Mark Harmon Exit

NCIS hasn't lost a beat since Mark Harmon left. The show was just renewed for a 21st season, which will mark its second full season without the actor who was once the face of the franchise. Harmon's Leroy Jethro Gibbs left partway through Season 19, with his final episode airing in October 2021. He was replaced by a new team leader played by Gary Cole, and the show has retained its crown as the most-watched scripted series on broadcast TV.

NCIS was among nine additional shows CBS renewed for the 2023-2024 TV season on Tuesday. NCIS: Hawai'i, CSI: Vegas, The Amazing Race, Lingo, Tough as Nails, 48 Hours, 60 Minutes, and Survivor were also renewed. Fire Country, Young Sheldon, Ghosts, The Neighborhood, Bob Hearts Abishola, So Help Me Todd, The Equalizer, FBI, FBI: International, and FBI: Most Wanted were also renewed.

The police procedural is the seventh-longest-running scripted U.S. primetime series in TV history. It is also the third longest-running scripted non-animated drama, behind only Law & Order: Special Victims Unit and the original Law & Order. The show's Feb. 27 episode, "Unusual Suspects," will be its 450th episode.

"It's pretty rare air that not many TV shows get to," Brian Dietzen, who has played Jimmy Palmer since Season 1, recently told TV Insider about reaching 450 episodes. "I'm not sure how many – you would probably know more so than I – shows have made it to this point. But I'll tell you what, when we were at our Season 1 wrap party, we didn't necessarily see this thing coming, being a show that had spun off of JAG and just trying our best to break into the top 30 shows that first year. And here we are at 450 and people still seem to be enjoying the show and we are having a hell of a good time producing it and acting in it." He later said the crew is "really proud" to continue making the series.

NCIS was created by Donald P. Bellisario and Don McGill as a spin-off of JAG. The show is now at more than double the length of that series, which wrapped after 10 seasons and 227 episodes. NCIS itself has three spinoffs, NCIS: Los Angeles, NCIS: New Orleans, and NCIS: Hawai'i. NCIS: NOLA lasted seven seasons, while NCIS: LA is in the middle of its 14th and final season. The NCIS: LA series finale will air on May 14. Paramount+ announced the first international spinoff, NCIS: Sydney, which will be available on the streaming platform outside Australia.

The current NCIS cast features Cole as Alden Parker, Rocky Carroll as Leon Vance, David McCallum as Dr. Ducky Mallard, Diona Reasonover as Kasie Hines, Dietzen as Dr. Jimmy Palmer, Katrina Law as Jessica Knight, Wilmer Valderrama as Nick Torres, and Sean Murray as Timothy McGee. New episodes air Mondays at 9 p.m. ET, with NCIS: Hawai'i following at 10 p.m. ET. The entire series is available to stream on Paramount+.