NCIS producer and star Mark Harmon knew he had found his young Leroy Jethro Gibbs from the first moment he saw him.

When Bridge of Spies star Austin Stowell came in to audition for the prequel series NCIS: OriginsHarmon recalled that he “felt the room shift a little bit” even “before he said anything.” Harmon recently mentioned it PEOPLE about the search for the younger version of the character he played for 19 seasons on the flagship series. “There was stiff competition there,” Harmon recalls. “There were a lot of good people. I’d say there were few people who attracted the attention that Austin did.

Harmon even recalled that Stowell “walked out and someone said, ‘I’ll just say it, that’s a movie star.'”

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Harmon played Leroy Jethro Gibbs, a former Marine Corps sniper who became a special agent and team commander for the Naval Criminal Investigative Service (NCIS) from 2003 to 2021. The long-running CBS procedure has already produced several spin-offs in recent years with varying degrees of success. years, from NCIS: New Orleanswhich Harmon co-produces NCIS: Los Angeles, NCIS: Sydneyand the recently canceled one NCIS: Hawaii.

A spin-off exploring the events that led Gibbs to his post at NCIS was announced in January, with Harmon on board to co-produce. After extensive speculation about who should play young Gibbs (with the exception of Sean Harmon, the actor’s son, who previously played a younger version of Gibbs on NCIS but returned to Origin solely as executive producer), Stowell was announced as the official choice in March.

Discussing the kismet of Stowell’s casting, Harmon noted, “I can say that about every role that was cast on this show because they all came in one after the other. We got everyone we wanted.” In addition to the Gibbs character, NCIS: Origins reprises the character of Mike Franks, the leader of the Major Case Response Team and mentor figure to Gibbs.

Muse Watson played the older Franks in the flagship series, while Kyle Schmid (being human, Big sky) was cast as Origin‘younger counterpart.

Speak with Entertainment weekly in September, NCIS writer and executive producer David J. North said the Origin team “just knew when Austin walked in that he was Gibbs… He embodied it. His talent is limitless – his dedication to the role, studying Mark, studying the show – he has a similar leadership quality that Mark had on the set that bleeds into Gibbs the character.”

“You always have everything about me,” the actor recalled to North and co-writer and executive producer Gina Lucita Monreal. “I just want to give it my all. I know what it means to the fans. I know what Gibbs represents to a lot of people out there. I know what the show represents to a lot of people out there, and I don’t want to let them down .”

As an extra show of confidence in the new series, Harmon himself steps back into the spotlight from behind the camera during tonight’s series premiere. Harmon will occasionally appear as the older Gibbs, recounting the past experiences that led him to join NCIS. Origin.

NCIS: Origins premieres Monday, October 14 at 9:00 PM ET/PT on CBS and streaming on Paramount+.