Harmon appeared in 437 episodes of NCIS across 19 seasons ... studying the show — he has a similar leadership quality that Mark had on set that bleeds into Gibbs the character.” NCIS: ...
NCIS: Origins will have not one, but two Leroy Jethro Gibbs in its premiere episode. It was announced by Deadline that MarkHarmon, the original Gibbs will make an appearance. Austin Stowell ...