‘NCIS’ Season 18 Finale: Did Bishop Leak NSA Files? Plus, [Spoiler] Is Blown Up (RECAP)

Emily Wickersham Ellie Bishop NCIS Season 18 Finale
Spoiler Alert
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[Warning: The below contains MAJOR spoilers for the NCIS Season 18 finale “Rule 91.”]

According to Gibbs’ (Mark Harmon) Rule 91, “when you decide to walk away, don’t look back.” And by the end of the NCIS Season 18 finale, someone does just that.

The episode has somewhat of a difficult task: tackle the fact that Bishop (Emily Wickersham) is being accused of leaking NSA documents, explain her not-that-recent very odd behavior, and advance the serial killer case Gibbs and Marcie (Pam Dawber) have been investigating. It does just that before ending on quite the … explosive note.

We break it down below.

Lara Croft, NCIS Agent?

As the episode opens up, the team’s in the middle of a shootout — and Bishop surprises McGee (Sean Murray) and Torres (Wilmer Valderrama) with her moves right out of an action movie, sliding across the floor and taking out two of the three bad guys with her remaining two bullets. (Torres doesn’t buy they were just lucky shots.) The third gets away.

Vance (Rocky Carroll) wants answers: they were supposed to just be doing an undercover gun buy. Things went awry, they explain to the director. But the good news is they trace calls made by the men Bishop killed to a landline. At the house, they find weapons stashed in a crawl space — along with NSA documents detailing an op where the U.S. used Syrian refugees to lure terrorists out of hiding. But who leaked those files? To everyone’s surprise, Vance reveals that a forensic back-trace identifies the person as Bishop.

Could it be the arms dealers were planning to blackmail Bishop? That’s not possible, NSA Deputy Director Ronda Ellis (Donzaleigh Abernathy) explains. The data was leaked 10 years ago before they were in the picture. Vance insists the NSA let NCIS conduct their own investigation, and in the meantime, he sends Bishop home.

Rather than follow his orders, she heads to see Gibbs, who’s painting “Rule 91” on his boat. It’s “the one that comes after 90,” is all he offers when she asks about it. She calls him out on his attitude lately (more on that in a bit) before returning to the office and leaving Vance gobsmacked when she tells him not to defend her anymore because “NSA’s intel is correct. I did it. I leaked the file.”

NCIS Season 18 Finale Bishop Gibbs Emily Wickersham Mark Harmon

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What Is Going on With Bishop?!

Bishop’s not done shocking her coworkers. She quits, too! She won’t answer Torres’ calls, and McGee knows that she’s facing more than just losing her badge by confessing to espionage. With Knight (Katrina Law) helping out by looking into the arms dealers’ last meals (to try to track the third), that frees McGee to chase after Bishop … to her car, in the parking lot. She hasn’t left yet. But their conversation doesn’t go as he expects.

The NSA program was wrong, she tells him. They used innocent people to go after terrorist leaders, and while there was a source claiming those refugees were foreign fighters, that person was unreliable. She regrets not leaking the documents sooner. She does feel guilty for betraying her coworkers, but she claims it’s in the past. It’s not for McGee, and the fact that she could bury that all these years makes him wonder: “What else don’t we know?”

Still, McGee wants to help her and turns to Gibbs for advice. Bishop is at a crossroads, his former boss says, and unfortunately, there’s nothing that McGee or Gibbs can do to help her.

The team can, however, continue to work the case, and they do track down that third arms dealer, who, after some sly work by Knight in interrogation, admits the stolen guns are his — but the NSA file is not. So whose is it?

That answer comes soon after Bishop talks to Gibbs (for the last time?). “You can do anything,” he tells her. He’s proud of her for following her gut and wants her to take care of herself. (Just how much does he know?) But before they hang up, she has a question: What’s Rule 91? “You’re living it,” he tells her. “When you decide to walk away, don’t look back.”

NCIS Season 18 Finale Bishop Torres Ellick

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It turns out Bishop is at ex-CIA instructor Odette’s (Elayn J. Taylor) — finally! — and this is all part of an op … that will truly begin once the (former) NCIS agent takes care of one loose end: Torres. He put the pieces together and tracked Bishop there. Yes, Odette planted the NSA documents, and yes, where Bishop is going, she needs to be a disgraced NCIS agent. She’s ready, and she’ll be gone “too long,” she shares. That’s why she blew him off.

“If we worked regular 9-5 jobs, things could be different,” she admits. “I didn’t mean for us to happen.” And with a “Goodbye, Nick” and a kiss, she walks away. Ouch. How are you doing, Ellick fans?

There’s No We in This Team

Marcie finds a pattern with the serial killer she and Gibbs are investigating: a victim is killed every 100 days. If that’s the case, another one should have been found last month. Gibbs advises her to look into missing persons case; maybe the body just hasn’t been found. But more worrisome is the fact that someone’s following Gibbs, who finds a bug in his basement and another in her office.

Though Gibbs wants her to leave the case alone, she, too tracks down the potential fourth victim, to the boat likely used to dump her body. And Gibbs finds pinecones at the scene that aren’t from the area of the dock. But that’s as far as he’ll let Marcie tag along.

NCIS Season 18 Finale Pam Dawber Mark Harmon Marcie Gibbs

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Is Gibbs Ever Returning to NCIS?

Meanwhile, Marcie finds Gibbs “pricklier” than usual in his basement and attributes it to him thinking his boat’s almost done. It needs a name first, she says, reminding him that it’s bad luck to launch without one.

And so Gibbs paints Rule 91 on it. When Bishop stops by to talk to him after Vance sends her home early on, she admits she’s mad at Gibbs because “we’re supposed to be a team, and you have kept us all in the dark.” They have no idea when he’s coming back, but he claims that’s up to Vance. But he can share if he’s decided to move on, she argues. He doesn’t outright deny that he has, so is it any wonder that she leaves the conversation thinking, “you’re not ever coming back, are you?”

The season ends with Gibbs on the water, in his boat (heading to check out the area where those pine cones are located?), smiling, happy, enjoying himself when … the boat explodes! But wait, there’s good news: Gibbs is alive and begins swimming away…

NCIS, Season 19, Fall 2021, CBS