The long-running military proceduralNCISbegan airing on CBS in 2003 and continues to be a hit for the network, bringing back longtime viewers and enticing new ones. The series has been so popular that it’s inspired several location-based spin-offs, includingNCIS: Los Angeles,NCIS: New Orleans,NCIS: Hawai’i, andNCIS: Sydney. However, the Fall 2024 season brought the newest addition to the franchise, and it’s nothing viewers have seen before.NCIS: Originsexplores the early career of fan-favorite character Leroy Jethro Gibbs, whose story everyone believed to be over.
Mark Harmon spent 18 years portraying the Naval Criminal Investigative Service’s Supervisory Special Agent in Charge Leroy Jethro Gibbs onNCIS. The actor left his iconic role behind in 2021, though he remained an executive producer of the series, and the leadership positionwas given to Agent Alden Parker (Gary Cole). Fortunately, the character wasn’t killed off the show but was said to be exploring a new life in Alaska, giving longtime fans some comfort that Gibbs was living on in theNCISuniverse. But what makes his character special enough to warrant his own spin-off? And how much more of his story is there to tell after nearly two decades on air? As it turns out, a lot.

Who is Leroy Jethro Gibbs?
Leroy Jethro Gibbs is a former U.S. Marine Corps Scout Sniper turned special agent for the NCIS. Since the beginning of the series, he led his team with a firm hand and quiet compassion, providing guidance and friendship to members likeField Agent Anthony DiNozzo (Michael Weatherly), Special Agent Ziva David (Cote de Pablo), and Forensic Specialist Abby Sciuto (Pauley Perrette), among many others. The epitome of stoicism, Gibbs is well-known for a set of fifty life rules that he lives by and also has a string of failed marriages and relationships behind him — influenced by his intensely private personality and reluctance to open up to anyone.
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However, the largest part of Gibbs' history that gives depth to his character is the death of his first wife, Shannon, and their daughter, Kelly, which occurred long before his tenure at NCIS. That trauma informs many of his characteristics, including his life rules, which were inspired by Shannon. Despite the nearly two decades that audiences spent with Gibbs and the occasional glimpse into his past, so much of his story has remained a mystery. Now, withNCIS: Origins, that has changed.

NCIS: Origins Casts Catch-22 Star as “Young Gibbs” in Prequel Series
NCIS: Origins will tell the story of Leroy Jethro Gibbs in the years before he became the character fans know and love.
NCIS: Originshas given Leroy Jethro Gibbs a new life, turning back the clock to 1991, shortly after the death of his wife and daughter. It focuses on a younger Gibbs as he takes a position as a Probationary Agent in the Naval Investigative Service, stationed at Camp Pendleton. Mark Harmon and his son Sean Harmon, who briefly played Gibbs in flashbacks onNCIS, are executive producers, along with showrunners Gina Lucita Monreal and David J. North, who have worked on the original series for many years.

In a press release, Sean Harmon, who came up with the concept forOrigins, said, “The character of Gibbs has been an important part of my life for 20 years, both in watching my father craft the role and previously having the honor to play young Gibbs myself. I always felt there was a tale worth telling about his earlier years, so I am thrilled to … tell this story and reveal a new side of this beloved character. However, a new actor has stepped into Gibbs' shoes — and Mark Harmon certainly left big shoes to fill.
Who Plays the Young Gibbs?
Austin Stowell was cast as the lead ofNCIS: Originsand given the tough task of taking on the role of a beloved character who has become almost synonymous with a different actor. Stowell made his TV debut in 2009 onThe Secret Life of the American Teenagerand quickly filled up his resume with bigger roles, both on television and in film. He has appeared in the critically acclaimedWhiplash(2014) and Steven Spielberg’sBridge of Spies(2015), among others, and his work as a Special Forces soldier in12 Strong(2018) likely helped prepare him for playing Leroy Jethro Gibbs.
NCIS: Originshas a much darker tone than the original series, and Stowell is well-aware that the trauma his character is experiencing over losing his family is an integral part of his performance. In an interview withVariety, he said, “The grief that he’s going through is not something that we can avoid. And as an actor, I’m someone who very much feels all of it.” He went on to explain why he was drawn to the role in the first place: “There were so many parallels to my own life — issues with suicide, a relationship between a father and a son, a feeling of imposter syndrome. It just feels right.” Luckily, Stowell hasMark Harmon, whose hands-on role includes narrating the series, to lean on to ensure his portrayal of Gibbs fits with the character that audiences have come to know over the years.

‘NCIS: Origins’ Brings Back More Familiar Characters
In addition to revealing more of Leroy Jethro Gibbs' personal past,NCIS: Originshas also brought back some other familiar characters, providing a backstory to some of his relationships with others that appeared in the original series. Among those is Mike Franks, who was portrayed as a mentor to Gibbs, directly responsible for helping him become an NCIS Agent, and often helped out on cases.
Originally played by Muse Watson, the role has been taken on by Kyle Schmid inNCIS: Origins, where he leads the Camp Pendleton Field Office. The first meeting between Franks and Gibbs is explored in connection with the deaths of Gibbs' wife and daughter, and part of the intrigue ofOriginsis to discover how their relationship eventually became what it was. Viewers also meet Franks' partner Special Agent Vera Strickland, who appeared inNCISSeason 11, originated by Roma Maffia and taken over by Diana Rodriguez. In another surprise,NCIS: Originswill finally answer a question fans have been asking for years, by revealing the history between Gibbs and FBI Agent Tobias Fornell (previously Joe Spano, now Lucas Dixon).

Actor Robert Taylor also has a significant part inNCIS: Origins, appearing as Gibbs' father, Jackson Gibbs (formerly played by Ralph Waite). OnNCIS,it was established that Jethro had an estranged relationship with his dad, whom he hadn’t had contact with since his wife and daughter’s funerals. As their relationship is a significant part of the story onOrigins, showrunners had to find a way to include the character in the series without disregarding the facts created by the original show. Luckily for them, the personalities of the Gibbs men lend themselves well to the idea that Jethro wasn’t completely honest about past contact with his father. The strained dynamic between them is an excellent way to showcase how Jethro became the hardened man we came to know and love onNCIS.
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Between his relationship with his father, his family’s death, and his new position under Mike Franks at Camp Pendleton, there is plenty of Gibbs' backstory to explore inNCIS: Origins— and that’s not including new twists and turns that audiences could never see coming. Introducing new characters that shaped Gibbs' decisions, revealing surprising truths, and exploring previously unknown events are just a few ways that the prequel adds new layers of intrigue. The show acts as a peek behind the curtain of one of the most secretive characters in theNCISuniverse, and the temptation to finally solve the mystery of Leroy Jethro Gibbs is sure to keep fans coming back until the story is over.NCIS: Originshas already been renewed for Season 2.