No story about the career of NCIS Special Agent Leroy Jethro Gibbs would be complete without his first boss, former Special Agent in Charge Mike Franks. Originally played on “NCIS” by actor Muse Watson, the younger Franks is portrayed in “NCIS: Origins” by Kyle Schmid, who is 40 years old at the time of writing.

Like his predecessor, Schmid imbues the character with a mix of charm and intentional political incorrectness, two of the qualities that made Franks one of the franchise’s most popular recurring characters. He is often blunt, extremely stuck in his ways, and more than a little misogynistic, but he is also charismatic, insightful, and always deeply loyal.

When viewers first meet Franks in “NCIS” Season 3, Episode 24 (“Hiatus Part II”), he has already been retired for 10 years and is plenty happy to be out of the agency (especially after he hears that a woman leads it). Now that the character is back at center stage on “Origins,” it seems like the perfect time for a little “NCIS” reunion. So, how might a 76-year-old actor reprise his 18-year-old role in a prequel? Of course, like many things on “NCIS,” Mark Harmon is the key.

For several seasons, Muse Watson was one of the show’s most consistent guest stars. In total, Watson played Mike Franks in a total of 20 episodes on the original series.

When Franks first appears in “NCIS” Season 3, he is largely used as an anchor to help guide Gibbs out of a period of amnesia, the result of a traumatic brain injury he suffered in the field. Before Gibbs recovers his memories, however, Franks is forced to remind Gibbs of the many events of the intervening years. This includes Franks’ choice to abruptly retire after the agency failed to heed his warnings about Osama bin Laden. After Gibbs recovers his memories and returns full-time to NCIS, Franks is eager to return to his retirement. 

However, despite his best efforts to stay away, he keeps getting pulled back into the organization, normally to offer a helping hand to Gibbs or a member of his team. For several seasons on “NCIS,” Franks pops up when you least expect it. Sadly, Franks dies at the hands of the Port-to-Port Killer in Season 8, Episode 23 (“Swan Song”), only for Gibbs to later learn that Franks had a terminal illness anyway. Most fans likely assumed that Watson’s time on the series was over at this point, but in fact, the actor would appear an additional eight times following the character’s death, usually portraying a vision only Gibbs could see.

He first appears to Gibbs in this manner in Season 9, Episode 14 (“Life Before His Eyes”), during which Gibbs reconnects with a variety of deceased characters from his past. Unfortunately, Watson’s ghostly role in the series came to an end after one last brief appearance in Season 15, Episode 8 (“Voices”).

Although 39-year-old Austin Stowell plays a younger Gibbs in the 1991-set series, Mark Harmon also portrays a deeply introspective Gibbs as the former agent lives out his retirement in Alaska. Through brief glimpses at the present day, we see the former federal agent attempt to write the story of his early days at NCIS (then called NIS). With Gibbs isolated and focused on the past, there will never be a better opportunity for Muse Watson to reprise his most well-known role.

On the original “NCIS,” Franks is a regular sounding board for Gibbs whenever the younger agent needs advice or counsel. In fact, when Gibbs retires for the first time at the end of Season 3, he chooses to reunite with Franks in Mexico. Now that Gibbs is well and truly retired, it would simply make sense for him to consider his old boss’ views on things.

Similar to what the original series did for most of his postmortem appearances, the older Franks could offer Gibbs a different perspective. Sitting across the campfire from his former “probie,” Franks might reflect on the full weight of his decisions from the afterlife. In addition to providing fans with a great serving of nostalgia, this would serve to remind viewers of the deep connection these characters’ younger counterparts will build in the coming years.

Written correctly, bringing back Watson to share a scene with Harmon could also make the latter’s role in the new series more than just ceremonial. For longtime “NCIS” viewers, this reunion would be a heartwarming nod to the legacy of the original show and a much-deserved recognition of Watson’s contributions to it.

While Leroy Jethro Gibbs and Mike Franks are the most prominent series regular characters on “NCIS: Origins” who first appeared on “NCIS,” they are not the only ones. In “Origins,” NCIS Special Agent Vera Strickland is portrayed by Diany Rodriguez, but the role was actually originated by Roma Maffia in “NCIS” Season 11, Episode 3 (“Under the Radar”). 

The prequel series has also introduced recast versions of Jackson, Shannon, and Kelly Gibbs. No other returning characters are confirmed at the moment, but considering the show’s willingness to recast central characters, there are plenty of faces from Gibbs’ past we could reasonably expect to see again.

First on many fans’ minds will be the late Jenny Shepard, originally played by Lauren Holly. According to legend, the future NCIS director gets to know Gibbs extra well during an undercover operation in Paris around 1999. While we see snippets of this relationship in the original series, her character is one of the few who never received a full flashback to show her first meeting with Gibbs. 

Another bit of “NCIS” mythology that fans will likely be eager to revisit is Gibbs’ three failed marriages between the time of his first wife’s death and the start of the original series. While we meet each of them at various points in “NCIS,” the precise circumstances of his wedding to each are somewhat clouded in mystery and seem like fertile ground for exploration.

Other possibilities for original series connections include beloved characters like former FBI Agent (and ex-husband No. 2 to Gibbs’ ex-wife No. 1) Tobias Fornell (Joe Spano), former NCIS Forensics Specialist Abigail Sciuto (Pauley Perrette), and NCIS Special Agent Stan Burley (Joel Gretsch).