For years, NCIS fans have wondered whether Mark Harmon would ever truly return as Leroy Jethro Gibbs. Now, they finally have their answer — and his comeback is much bigger than a quick cameo.

Harmon is returning on-screen as Gibbs for Season 3 of NCIS: Origins. According to reports, he is expected to appear in every episode of the season, giving present-day Gibbs a season-long storyline alongside the prequel’s story of the younger Gibbs, played by Austin Stowell.

The news is especially significant because Harmon stepped away as a regular on the original NCIS in 2021. Although he remained connected to the franchise and later made appearances, many longtime viewers had wondered whether they would ever see Gibbs become a major part of an NCIS story again.

Now CBS has begun teasing exactly that. A recently released preview features present-day Gibbs and a mysterious message about how, no matter how far someone goes, the past can never completely be left behind. The teaser has already sparked an emotional reaction from longtime fans.

And there may be much more behind Gibbs’ return than simple nostalgia.

NCIS: Origins explores the events that shaped Gibbs decades before viewers first met him on NCIS. Bringing the older Gibbs directly into the story creates an opportunity to connect his present life with memories and unanswered questions from his younger years.

For viewers who followed Gibbs for nearly two decades, that could make Season 3 one of the most personal chapters of his story yet.

Mark Harmon may have walked away from the NCIS office years ago — but Leroy Jethro Gibbs clearly isn’t finished.

NCIS: Origins Season 3 is scheduled to premiere October 6, 2026, with Harmon beginning his expanded season-long return.