NCIS: Origins dives into Gibbs' past to a time before the creation of NIS. As a man who rarely gets personal, Gibbs is showing the most vulnerable side in the prequel, which is what the series is ...

Mark Harmon's Gibbs is such an iconic NCIS character, and his list of rules cemented him as one of the best. Although Harmon's Gibbs left NCIS in season 19, he remains a vital character to the show.