NCIS: Origins Finally Explained The Origin Of Gibbs' Infamous Headslap

Contains spoilers for "NCIS: Origins" Season 2, Episode 18 — "Hollywood Ending"

Have you ever wondered where Leroy Jethro Gibbs' (Austin Stowell) infamous head slap originated from? It turns out the habit comes from a gesture made by his dear friend, Mike Franks (Kyle Schmid). While Gibbs mentions the fact that he got his head-slapping tendencies from a mentor back in the "NCIS" episode "Hiatus Part 1," "Hollywood Ending" shows us the actual moment. Franks slap Gibbs the same way Gibbs backhands others after he catches Gibbs, Lala Dominguez (Mariel Molino) and Bernard "Randy" Randolph (Caleb Foote) consulting a large map of the world and contemplating where they want to be transferred when the Camp Pendleton office is shut down. Franks is hoping to get Gibbs and the others to concentrate on their case — and it's a tactic that works, at least for the moment.

Gibbs isn't the only one who's distracted. A few moments later, the slap is referenced again when Randy asks Franks about a possible deferment to the Naples, Italy branch of the NIS. Annoyed by Randy's focus on the future, Franks retorts, "don't make me slap you upside the head like I done to Gibbs. I don't want that becoming a thing." 

But "NCIS" fans know that it definitely becomes 'a thing' in the future, with Gibbs smacking everyone from Jimmy Palmer (Brian Dietzen) to, well, himself. But there's one member of the crew who ends up taking the brunt of his aggression more often than the others.

While almost every member of Gibbs' (played by Mark Harmon on "NCIS") team has experienced a good hard knock to the noggin from him, there's one special somebody who tends to draw most of his ire. Tony DiNozzo (Michael Weatherly) tends to get slapped by Gibbs the most frequently, usually because he can't still his tongue and won't resist making a smart remark or a pop culture reference. As a matter of fact, during a flashback where the characters meet for the first time in Season 8's "Baltimore," Gibbs slaps him. It gets to the point where Tony feels incomplete when Gibbs greets him with anything but a rap to the head — leading to several Gibbs and Tony scenes that "NCIS" fans love.

Several of the twosome's colleagues echo Gibbs' tendency to slap Tony on the head — including Abby Sciuto (Pauley Perrette), leading to some of her most pause-worthy moments on "NCIS" as Tony winces or grins in response to her blow. Just goes to show why everyone should stay on Gibbs' good side — it looks like his fondness for slapping is contagious.