Inside 12 rules NCIS Special Agent Gibbs’ lives by – from how to keep a secret to knowing when you’re wrong

Mark Harmon, who played Gibbs, was one of the last original cast members left on NCIS, having been on the show since its first season. His final appearance was in 2021 on episode 4 of season 19, “Great Wide Open,” when he retired to Alaska. He left behind his legacy through his 91 rules, which have not all been revealed yet.

“My wife believed we all should have a code to live by, a set of rules,” Gibbs said via voiceover on the third episode of the prequel spinoff NCIS: Origins, which follows his early days with the Naval Criminal Investigative Service. “And I believed in her. So for years, I wrote my own rules down on napkins, scraps of paper. I followed all of them to the letter.” Here are 12 of those rules,