Uncovering Gibbs' Darkest Storyline: The NCIS Prequel Spinoff

The Return of Mark Harmon and the NCIS Prequel

Mark Harmon's upcoming NCIS prequel spinoff will finally show Leroy Jethro Gibbs' darkest storyline 18 years after it debuted. More than two years since he left the CBS police procedural, the actor is slated to return to the franchise — this time, in a slightly different manner. Instead of playing his iconic role on the screen, Harmon is set to narrate the NCIS prequel that tackles Gibbs' early days as a member of the organization. He will produce the project with his son, Sean Harmon, who once played a younger version of Gibbs in the main show.

Mark Harmon as Gibbs and Mary Mouser as Kelly in NCIS

Harmon exited in NCIS season 19, but like many cast departures from the series, the CBS show has left the door open for his potential return. Instead of being killed off, Gibbs simply decided to walk away from the job, opting to stay in Alaska and pursue his passion for fishing. Throughout Harmon's time in NCIS, the weekly cases were intertwined with personal arcs, including Gibbs'. Despite his closed-off demeanor, it established some big moments in his life — some of them were quite tragic. Considering the premise of the new NCIS offshoot, it has the chance to properly tell arguably his most harrowing experience.

Leroy Jethro Gibbs In NCIS

NCIS’ Prequel Time Setting and Gibbs’ Tragic Past

The main NCIS series showed how Gibbs ended his storied career, but the prequel will tackle how he got his start after being in the Marines. Per the premise, the NCIS spinoff will take place in the early '90s, during his time being stationed at Camp Pendleton. Assuming that it will stay true to the established canon of the primary show, then it's also around the time when his first wife, Shannon, and daughter, Kelly, were murdered. Their existence wasn't laid out until NCIS season 3, and even though the incident was revisited and even became the jumping point for some subsequent arcs, it never properly played out on screen.

For context, Shannon and the then-eight-year-old Kelly were murdered by a Mexican drug dealer named Pedro Hernandez during the final official day of Operation Desert Storm before the events of the original NCIS series. At that point, Gibbs was still an active member of the Marine Corps, so he wasn't around when they were brutally killed. As it turns out, Shannon supposedly witnessed the murder of a Marine at Camp Pendleton, where Gibbs was based at that time, which led to their untimely and tragic demise.

The Impact of Gibbs’ Family Tragedy on the NCIS Prequel

Like most police procedurals that got their start in the late '90s and early '00s, NCIS never shied away from tragedies. The team has had their fair share of losses over the years, with some of their own members even dying on the job. That being said, the death of Gibbs' family is still such a dark arc. After Shannon and Kelly's murder, Gibbs was married three more times — all leading to ugly splits. In the end, he continues to be haunted by their deaths, and to ground the show on that, means that the NCIS prequel may be darker than its parent series.