Mark Harmon’s portrayal of Leroy Jethro Gibbs is one of the most enduring character performances in TV history. From the moment Gibbs stepped onscreen in NCIS’s first season, it was clear he wasn’t the stereotypical loud or flashy boss. Instead, Gibbs led with quiet authority, razor-sharp instincts, and a personal code that his team came to rely on — and fear just a little.
His style of leadership was defined by action over words. Gibbs didn’t explain himself much, but when he did, his advice stuck — often in the form of the now-famous “Gibbs’ Rules.” These rules became a cultural touchstone for fans, from “Never let suspects stay together” to “Always be specific when you lie.” Then there was the infamous “Gibbs Slap” — a quick tap to the back of the head meant less as punishment and more as a reminder to stay sharp.
Part of what made Gibbs so compelling was his complexity. Beneath the stoicism was a man haunted by personal tragedy — the loss of his wife and daughter — which fueled his relentless pursuit of justice. Harmon played this duality with a subtlety that kept audiences glued to the screen.
Even after Harmon’s departure from the main cast in Season 19, Gibbs’ presence is still felt. His name comes up in conversations, old cases resurface, and fans continue to hope for a surprise guest appearance. In many ways, Gibbs is NCIS — and his legend will likely endure as long as the show itself.
