Before Mark Harmon was cast as Leroy Jethro Gibbs on “NCIS,” several A-list actors were considered for the role. These included notable names such as Harrison Ford, Alec Baldwin, Chris Cooper, Clive Owen, Kevin Bacon, Tom Berenger, Val Kilmer, Charlie Sheen, Aidan Quinn, and Patrick Swayze. Among these, two Oscar winners were Harrison Ford and Chris Cooper. Ford, a significant name in Hollywood, was mentioned in early casting discussions but never formally approached. Cooper, another distinguished actor, was also considered during the casting process.