Mark Harmon is returning to NCIS.

CBS reveals that NCIS: Origins, a new spin-off to the world’s most successful television franchise, will see Gibbs’ early years explored and narrated by OG series star Harmon.

The new series, executive produced by Harmon, Sean Harmon, Gina Lucita Monreal and David J. North, will find a place on the official CBS 2024/25 broadcast slate, so fans won’t have long to wait for a first look.

Set in 1991, NCIS: Origins takes place prior to the events of NCIS and follows a young Leroy Jethro Gibbs who starts his career as a newly minted special agent at the fledgling NCIS Camp Pendleton office where he forges his place on a gritty, ragtag team led by NCIS legend Mike Franks.

“We are elated and honored to continue the expansion of the NCIS universe in such a unique and unexpected way,” said Amy Reisenbach, president of CBS Entertainment. “Viewers can look forward to Mark Harmon returning to CBS to narrate the complex and mysterious backstory of Leroy Jethro Gibbs’ early years in NCIS: Origins, which will build on the rich legacy of this character while reintroducing fan-favorite characters and meeting new ones.”

“There’s no denying the cultural and global phenomenon of the NCIS franchise for the last 20 years,” said David Stapf, president of CBS Studios. “When Sean and Mark approached us all with this exciting expansion of the universe – exploring a young Gibbs – we knew it was the next story that needed to be told. We also couldn’t be luckier to have Gina and David at the helm as co-showrunners who are not only brilliant and adept writers, but know this character and universe so well.”

“We’re thrilled to be bringing this new chapter to life along with Mark and Sean Harmon,” said executive producers and co-showrunners Gina Lucita Monreal and David J. North. “This really is the making of Leroy Jethro Gibbs. And even the most dedicated NCIS fans will discover that they don’t know the whole story.”

“The character of Gibbs has been an important part of my life for 20 years, both in watching my father craft the role and previously having the honor to play young Gibbs myself,” added executive producer Sean Harmon. “I always felt there was a tale worth telling about his earlier years, so I am thrilled to be stepping into a producing role alongside Gina, David and my dad as we tell this story and reveal a new side of this beloved character.”

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