Probationary Agent Ned Dorneget gets his implant pulled. The doctor finds it's not actually a regular implant -- it's a listening device.
"Wait, somebody bugged my mouth?" he says.
Palmer comes up looking for intel on his bachelor party Abby planned. McGee tells him to be up on his hepatitis vaccinations and get a good helmet. Tony suggests kneepads. They don't actually have any idea what she's up to.
Dorneget comes in with his tooth.
Abby examines it. Dorneget says it was there for years, but a couple of weeks ago he got a call from a dentist, not his usual one, saying there was a recall on his implant. When he got a popcorn kernel stuck it recently he went to a new guy to have it dealt with.
The tooth bug had a short range, but used the pressure of his chewing to stay charged. It's fancy tech and Abby checks for a patent. She finds ones from 18 months ago filed by Harper Dearing.
They're after Dearing for the arsons exploiting bad ship wiring. Samantha Ryan (Jamie Lee Curtis) shows up with NSA intercepts of Dearing's last communications with the venture capital firm President Vincent Maple.
Tony and Ziva visit Vincent Maple and show him his email from Dearing in which Dearing mentions surfing somewhere he once went with Maple. Maple says it never happened and he's on their side, he suggests Dearing is losing it.
Sam and Gibbs talk to the dentist who put in Dorneget's new implant, Dr. Berman. He says he didn't know there was a bug in the tooth and he doesn't know Dearing, but Sam says he's lying about both things. McGee interrupts, saying Dearing is on the phone for Berman.
They take him to MTAC. Dearing gives Berman permission to answer their questions, but says he's calling to speak to Gibbs. Dearing says "this is all his fault."
Tony and Ziva come in to see agents sweeping the whole building for bugs. They want to know how he knew Berman was there and how he broke through MTAC's firewall.
Sam thinks he's a sociopathic paranoid narcissist.
Palmer walks by on the phone with Brinna, telling her he doesn't know why Abby asked him what kind of tattoo he wants to get.
McGee reports Berman says he was threatened to implant the bug and got $10,000 for it. He has a description of the man who approached him.
Sam checks that Gibbs knows it's not really his fault, although it seems clear Dearing believes it.
Palmer goes to Abby, trying to convince her to postpone his bachelor party. She says she already put down a non-refundable deposit on 50 gallons of scented body lotion.
She runs Dearing's face through facial recognition and gets a live hit. He's in a Navy yard sitting openly on a park bench.
NCIS locks it down but doesn't find him. He came in with only a briefcase.
They see he left a flower on the bench. Gibbs sees it came from a nearby bush and walks over. He finds a model of his boat, down to the name and rudder.
Later that night, Sam admits she likes Dearing's style. "Of course you do, it's yours," Gibbs says.
Gibbs and Ryan try to suss out his motivation. She mentions that Dearing's son was killed in a suicide attack on a Navy ship. There was an early warning system that could have stopped it, but it hadn't been replaced yet on his ship.
Sam thinks Dearing is trying to teach the Navy a lesson. She thinks Dearing has more plans for Gibbs.
Gibbs asks Sam how long she's known about Dearing's son. He's frustrated again about her keeping secrets.
"You want me to let you in, then let me in," she says.
Tony calls with a report that they found the car of the guy who bullied Berman. It's registered to Frederick Fountain, a former cop who served time for taking bribes. Tony thinks he interrupted Gibbs with Sam.
Gibbs pops in the back seat.
They see Fountain and chase him. They catch him quickly and he says he'll tell them anything, even about the next attack, if they get him out of there.
But then two shots ring out and Fountain is shot dead.
Down in the morgue, Duckie tells Palmer that Abby asked to borrow the rotary saw for his bachelor party.
Abby found traces of RDX explosive from under Fountain's fingernails. The bullets shattered on impact.
Duckie shows Gibbs a Watcher Fleet microchip he found in Fountain's arm that was recently put in.
The microchip is the same one that was in Agent Leven's arm last year. The info on it is in code. It shows balance sheets from Dearing's company showing purchase of building materials.
Gibbs and Ryan bring a hard copy of it to Maple. He says they have no record of the purchases. He looks at the items and suggests Dearing is either building something for the spaceship or Naval artillery shells.
Ryan thinks of something. One of the weaknesses the Watcher fleet found was that some guns that used RDX could explode if the right artillery wasn't used. They could take out half of their fleet just during exercises.
Back in the lab, Abby runs simulations that show how bad the explosions could be. Dorneget tells Gibbs he found an encryption key while doing data entry on his tooth bug. The key is how Dearing hacked MTAC. They traced it to a cell phone.
Gibbs dials the number and Dearing answers, knowing it's Gibbs.
Gibbs asks Dearing what his son would think of what he's doing. Abby runs a trace. Dorneget recognizes the address from the shipping manifest. They think they've found his warehouse.
The team heads there, guns drawn, but finds an empty warehouse with just a security guard inside. He's pushing a briefcase full of cash.
Back at the office, they send out alerts about the defective artillery. The security guard has no record, but he had $1 million in cash.
In interrogation, he insists he had no idea what was in it. He got a small case once a month and a truck would come pick it up. He got a text to deliver the case to an address tonight.
They check the guard's cell and finds it's registered to a Dearing holding company. They want to use the guard for a sting and have him deliver the case as planned.
Abby comes in in a circus master of ceremonies sequined outfit and mustache, ready for the bachelor party. They think it's canceled, but Gibbs says it's not.
Cut to the team doing shots in a bar and playing quarters. Gibbs is winning, naturally. Ziva watches over the guard out on the street as the guys drink it up inside.
Jimmy makes a toast. "As Nathaniel Hawthorne once said: 'Let man tremble at the hand of woman....' Blah, blah, blah -- alcohol is fun."
Tony checks with Dorneget; they're drinking apple juice. Palmer stumbles. The limo pulls up outside and they converge on it. They find Vincent Maple inside.
Back at interrogation. They found him with no bags, a fake ID and a one-way ticket to Morocco. He insists he doesn't know where Dearing is.
He confesses there was no equipment, he set up a dummy account to siphon money out of Dearing's company. "I was embezzling, that's it," he says.
He reminds them the faulty artillery was Ryan's idea and he just went with it.
"The real question you should be asking is how'd you get a copy of my books?" he asks.
Back in the office, they go back over Fountain. They found his car thanks to a tip, which they traced to Dearing. He wanted them to find Fountain and the chip.
They think Dearing knew Maple was embezzling and used it to send them on a wild goose chase.
Gibbs goes to Sam with a stern face.
He wonders if her defective artillery theory was really a mistake. She asks him what he's insinuating. He gets frustrated that he can read everyone but her. For such an intuitive introvert, she knows it drives him nuts.
Gibbs gets a text from Dearing saying "Check." He calls Tony.
Director Vance has disappeared.