11 Actors Were Considered to Play Leroy Jethro Gibbs on ‘NCIS’ Before Mark Harmon Was Cast (Including Two Oscar Winners!)

When NCIS premiered in 2003, the role of Special Agent Leroy Jethro Gibbs—Mark Harmon’s career-defining character—was anything but a sure thing. Before Harmon became the anchor of the series, a remarkable range of big-name actors, including two Academy Award winners, were on the shortlist. Here’s who was considered and a peek into how the casting ultimately came down to Harmon.

1. Scott Glenn

Original frontrunner for Gibbs—and interestingly, for Ducky as well—Scott Glenn was a strong contender. A respected film actor known for serious roles, he ultimately passed on the NCIS opportunity SlashFilmLooper.

2. Harrison Ford

Yes, that Harrison Ford. Though the odds of scoring him were slim, his name popped up during early brainstorming sessions—a reflection of the team’s ambition SlashFilmLooper.

3. Alec Baldwin

On the initial whiteboard of possibilities, Baldwin’s name appears. He was discussed—but no formal offer was made SlashFilmLooper.

4. Chris Cooper

Another well-respected actor considered, but again, he wasn’t actually approached with an offer SlashFilmLooper.

5. Clive Owen

Owen’s name surfaced in early thinking, but like many others, the idea never progressed beyond speculation SlashFilmLooper.

6. Kevin Bacon

Despite his fame, Bacon was merely on the list—not formally pursued SlashFilmLooper.

7. Tom Berenger

Another name tossed into the mix early on—interesting, but no offer extended SlashFilmLooper.

8. Val Kilmer

Part of those brainstorming discussions, though the idea never progressed to negotiations SlashFilmLooper.

9. Charlie Sheen

The Two and a Half Men star was considered. Again, a name in discussion only, without formal outreach SlashFilmLooper.

10. Aidan Quinn

Yet another option floated informally—hints of potential, but no advances made SlashFilmLooper.

11. Patrick Swayze

On the speculative roster, but, like others, never contacted for an offer SlashFilmLooper.

So Who Were the Oscar Winners?

While none of the above were confirmed Oscar winners, two heavily esteemed actors on that speculative list—Chris Cooper and Harrison Ford—are Academy Award recipients, making them the likely references to the “two Oscar winners” mentioned in some reports SlashFilmLooperWikipedia.

How Mark Harmon Became Gibbs

As the original dream cast list fizzled, casting director Susan Bluestein stepped in with a bold counter-suggestion: what about Mark Harmon? After seeing his performance in The West Wing as a Secret Service agent, series creator Don Bellisario knew he’d found the right voice for Gibbs. Harmon met with Bellisario, and the chemistry was instant—Gibbs was born SlashFilmWikipedia.

Bellisario later said, “I said, ‘Oh, my God, he’s Gibbs.’ He had matured. He’s good-looking in a totally different way than he was as a young guy.” Wikipedia.

Why It Matters

This reveals how casting is often less about checking boxes and more about finding the soul of a character. Instead of chasing name recognition, the creators let chemistry and fit guide their decision—and that intuition made all the difference.

** Recap Table: Who Was in the Running for Gibbs**