Mark Harmon is about to celebrate a major milestone.

On September 2, the actor millions of television viewers still know simply as Gibbs will turn 75 years old.

But longtime NCIS fans aren’t only looking back at Harmon’s extraordinary career.

They’re looking ahead.

After stepping away as a series regular on NCIS in 2021, Harmon remained closely connected to the franchise as an executive producer and narrator of NCIS: Origins.

Now, Gibbs is moving out of the narration booth and back in front of the camera.

Harmon is set to appear as the present-day Leroy Jethro Gibbs throughout Season 3 of NCIS: Origins.

And this isn’t expected to be just a nostalgic cameo.

The new season will follow an ongoing present-day mystery involving Gibbs and something connected to his past at Camp Pendleton.

That means viewers will once again get to watch Harmon actually play Gibbs as the mystery develops.

For fans who followed the character for nearly two decades on the original NCIS, it’s a significant change.

Harmon may be turning 75, but he clearly isn’t finished with the character that made him one of America’s most recognizable television stars.

Season 3 of NCIS: Origins premieres October 6.

And after years of wondering whether Gibbs would ever truly return, fans finally have another reason to start counting down the days.