'NCIS' Episode 400 Digs Into Ducky & Gibbs' Backstory

Mark Harmon Leroy Jethro Gibbs David McCallum Ducky NCIS
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There's nothing quite like steely NCIS boss Leroy Jethro Gibbs (Mark Harmon) in crusader mode. He's a man on a mission in the military procedural's opening five episodes, a storyline starting in late 2019 that explains the lingering mystery of where Gibbs went back in Season 17 when he got a text and suddenly excused himself from a case. He told colleagues he was going fishing — but returned a few days later with a black eye! 

Turns out he and buddy/ex–FBI agent Tobias Fornell (Joe Spano) were pursuing the Canadian dealers who sold counterfeit opioids to Fornell's daughter, Emily (Juliette Angelo), leading her to overdose and nearly die in the Season 16 finale. "They bring different energies to this chase," says NCIS executive producer Steven Binder. "Gibbs has a bug up his butt about breaking the law and causing all sorts of chaos in communities with the drug situation. Fornell's daughter has been hurt by this epidemic, so he's a little more fiery."

Each episode also checks in on the NCIS team as they continue working despite Gibbs' distraction. (The opening moments of the premiere find them in an extremely screwed-up situation!) One case involves treasure hunters, another a surprise for Special Agent Tim McGee (Sean Murray) and wife Delilah (Margo Harshman) while on their first vacay since having twins.

In the fifth episode, the Gibbs-Fornell quest bursts into the bullpen. "Gibbs is working on the side on this thing until it comes to the forefront. Then he can't hide it anymore," Binder reveals.

If that's not exciting enough: Episode 2 also happens to be the long-awaited 400th. It's packed with cool backstory, flashing back to 1980 and the first meeting of young Gibbs, played by Mark's son Sean, and medical examiner turned historian Ducky (David McCallum/Adam Campbell). Says executive producer Frank Cardea, "Ducky's been Gibbs' confidant for 17 [seasons]. We'll have a better understanding why."

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NCIS, Season 18, Fall, CBS