Mark Harmon guides new chapter for Agent Gibbs as producer for "NCIS: Origins"

Mark Harmon, widely known for playing Special Agent Leroy Jethro Gibbs on the hit CBS drama "NCIS," is stepping behind the camera as the executive producer and narrator of a new spin-off prequel, "NCIS: Origins."

After nearly two decades in the role, Harmon is now helping bring to life the early years of Gibbs, with actor Austin Stowell portraying a young version of the iconic character.

"You come in and audition here for years and years, and all of a sudden, you're presented with a badge with your name on it," Stowell said about now working on the Paramount lot.

The show's set features scenes at Camp Pendleton, including locations like Daley's Tavern, a bar just off-base. For Stowell, it is a role of a lifetime.

"I felt very confident in what I could bring to the character, and then the second you walk in the room, that all goes out the window," Stowell said.

Casting the role of young Gibbs in "NCIS: Origins" was a significant decision for the team, as it meant finding someone to take on the character that Harmon made iconic. The prequel, set in 1991, explores Gibbs' early days as a rookie agent.

Harmon saw the project as an opportunity to dive deeper into the character's backstory, introducing a Giibbs that has never been seen before in the original series.

"This is a chance to really kind of dig into it," said Harmon

The role also brings a more personal and emotional storyline for Gibbs, one that explores his grief after the loss of his wife and child.

"He's in rough shape," Harmon said.

Stowell has drawn on his personal experiences to portray Gibbs' pain. His father died by suicide four years ago.

"Loss is something we all deal with and for Gibbs, this is something that has cracked him to his core, said Stowell.

Harmon has been a steady presence on set, offering guidance to Stowell and the rest of the cast.

"From day one, Mark has been available," Stowell said. "He's so good at allowing the people who are on this show to feel like they are supported."

Harmon made it clear that this new chapter of "NCIS" belongs to the younger cast.

"I'm there to help and to talk to them or to tell them what I remember from being in this for a while. But this is their thing," Harmon said.