Series creator Donald P. Bellisario initially did not think Mark Harmon would fit the role of Gibbs, a "flinty type with a strong sense of honor and respect for the military", but changed his mind after viewing a tape of Harmon's portrayal of a Secret Service agent on The West Wing. Co-executive producer Charles Floyd Johnson recalls, "We all looked at that work. And everybody said, 'He's Gibbs.'" The production also considered Harrison Ford, Scott Glenn, Kevin Bacon, Chris Cooper, Alec Baldwin, Val Kilmer, Clive Owen, Tom Berenger, Charlie Sheen, Aidan Quinn, and Patrick Swayze; with Glenn being strongly considered. Harmon was cast in 2003, and Bellisario explained, "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." At another point, he said, "I am so lucky to have Mark Harmon as the lead. You have no idea. This cast is gold. Mark Harmon is a Middle American guy, even if he was raised in Southern California. His values are exactly the same as mine."