Two civilians find the body of a Navy petty officer first-class, submerged in a backyard hot tub; Gibbs and company investigate; Ducky sees an unusual clue. The widow fills in Tony and Ziva, and Abby makes a significant discovery, implicating a ship of the Royal Navy. Gibbs takes a strong dislike to a major in the Royal Marines; however, Ziva asks the major to "do a quickie". Tony and Ziva find an important valve handwheel, and Gibbs gains an advantage by using a pipe wrench. The ship leaves port, but the major stays behind, and the major turns out to be something else, as does a special agent of the CIA. Vance tells Gibbs to cool it; Gibbs takes a different tack, and he finds a visitor when he returns home. The gang trace missing money; they figure out who killed the sailor, and who stole the money, then they nab the person responsible. Tony sets off an alarm.
The body of a petty officer shows up in a hot tub; Gibbs and company investigate; Ducky sees an unusual clue; Abby finds a link to the Royal Navy. A Royal Marine major and a CIA agent prove to be something else. The gang catch the bad guy.
- A realtor waits for a hot tub guy to clean out the disgusting tub so he can sell a foreclosed house. The guy drains the tub -- and finds a dead Sailor inside.
Ziva busts Tony snooping on her computer. He wants to know about the guy in Miami she's been flirting with. Gibbs comes in to announce the dead body of the week.
The victim is Petty Officer First Class Edward Bick. Gibbs sends McGee in the tub to fish him out. Palmer finds a through and through bullet hole. They find his stomach was slit open.
Tony and Ziva go to interview his widow, Tara. As they're talking to her a Marine named Jason Crosby pulls up. They were stationed on the Lockwood together. He says he knew something like this would happen. Tara tells them Ed was selected for a special duty assignment -- but not on the ship. He thought he was being watched.
In the morgue, Duckie tells Gibbs the victim drowned violently, and not in the hot tub. He doesn't know why he was shot after.
There's some sort of allergic reaction in his lungs. There's an imprint of something metal on the side of his head. Duckie finds something between the victim's teeth -- a piece of a $100 bill.
In the lab, Abby has matched the bullet fragments they found in the railroad tie behind the tub to a rare English Webley gun.
The water in his lungs was salt and fresh water and had metal shavings and cleanser not used on American ships.
McGee reports that Bick was working on something with the CIA that they can't access.
In the lab, Abby has matched the mark on Bick's head to a valve on a ship made by Barrish Industries, out of Liverpool. They make transport vessels for the British Royal Navy. The only British ship in the yard is the Sparrowhawk, technically British soil.
Vance introduces Gibbs to Major Malloy, liaison between British and US Navy. The boat is supposed to leave within hours and he says it can't be delayed.
"Good luck getting out of port," Gibbs says, leading to snotty fight. Vance calls the Sec-Nav.
Malloy introduces himself to Gibbs' team, laying on the charm. Vance tells him the Sec-Nav has given NCIS permission to board the Sparrowhawk.
In the lab, Abby shows Gibbs that the money found in Bick's mouth was coated in florescent powder, which would get on anyone who touched it. Bick was covered in it, meaning he swallowed at least one entire bill.
She runs something over it and shows it's also emitting radiowaves. If they knew the frequency they could track the cash and anyone who touched it for miles. It's CIA technology, so that's where they have to go.
Gibbs goes to see CIA Agent Tennison in Norfolk. She says she doesn't know Bick. He shows her the bill. He thinks someone stole CIA money in Norfolk and killed Bick. She tells him about a cash shipment scheduled for Afghanistan under British oversight -- but says the mission was scrubbed.
McGee calls to tell Gibbs that Malloy is at British HQ trying to get permission to set sail.
Ziva and Gibbs intercept Malloy, who tells them British fleet command has just requested they leave immediately. Ziva asks for just a few minutes.
She and Gibbs check out the ship. They find the valve based on the ship plans Abby sent. There's standing water nearby, enough for Bick to have been drowned in. Malloy comes to hustle them off. An alarm goes off -- they have to run a diagnostic. Malloy's going to investigate when he runs into Gibbs.
After Malloy leaves, Tony thinks the alarm was a lucky break. Luck had nothing to do with it -- Gibbs shows them his wrench.
Later, Malloy accuses Gibbs of sabotage. The captain reports the issue has been fixed.
Tony and Ziva head back to the crime scene where they turn on black light and find the tracking powder all over the place, including on a container.
Gibbs shows Tennison the photo of the dust, saying she lied. She says the ship was used to transport money on previous mission, but he says the Sparrowhawk has never been to the Middle East. He tells her Bick swallowed some of the money. She finally tells Gibbs she worked with Bick. Only three people knew the money was there: her, Bick (who was in charge guarding it) and the Brit responsible for the money drops. Malloy. $3 million is gone.
McGee calls to say surveillance shows Malloy leaving the yard minutes after Bick was murdered. His phone records put him a quarter mile from where Bick was dumped. Gibbs tells McGee to send a helicopter for Malloy.
Back in interview, Gibbs asks Malloy where the money is. He admits owning a Webley gun. Gibbs points out his flat in London is in foreclosure. Malloy points out Gibbs doesn't have the cash, murder weapon or witness.
In the lab, Abby still can't ID whatever caused Bick's allergic reaction, but she got a print of the tea bag Malloy was using that Gibbs swiped. He's not in the NATO or British Naval databases. He's MI-6, an attaché to the Sparrowhawk.
Gibbs comes to the office to find Malloy has left with someone from the British consulate. His phone's off so they can't track him, but they find he made calls from The Drake earlier.
At the hotel, Gibbs, Ziva and Tony go in his room but find it empty. Black light shows traces of the tracking powder. They money was there.
Back at the office, they put out a BOLO for Malloy and all agencies are on alert. Vance comes to tell Gibbs the CIA wants the case to go away because the money was for groups in Afghanistan that we're not supposed to be in business with.
Gibbs goes home to find Malloy sitting on his couch drinking beer. He tells Gibbs he needs his help. He claims he was set up. The money was on the ship. He gives Gibbs a wad of cash, enough to track the CIA frequency -- and to the person responsible. Gibbs gives him back the piece of the ship he took.
Gibbs takes Malloy into the office, where Tony warms to him discussing Peter Sellers and Dudley Moore.
In the lab, Abby shows Gibbs pollen she found in Bick's lung tissue, found only on Diego Garcia Air Force Base -- where Bick has never been. So the pollen was transferred by whoever had been there when they killed him.
Upstairs, they look at the base layout and ID a CIA HQ. They look to see who the most recent station chief was there: It was Agent Tennison.
In MTAC, they wait for CIA to activate the cash-tracking software. It shows up all over town -- it was used to pay the British sailors, which get paid in US cash. They spent it.
They find Tennison recently arranged to go to the USS Tripoli. She called Lt. Malcolm Dufresne on board several times, they think he's her contact to switch out the money.
On the ship at night, a helicopter lands carrying Tennison. She has a large briefcase. She goes to see Dufresne, but finds Malloy instead. Tennison pulls out her Webley pistol and threatens Malloy. Gibbs comes out to arrest her.
She protests that the money was going to drug smugglers and opium growers and she may have been saving lives by keeping the cash.
At the office, Ziva emails someone. Tony wheedles her for information, saying maybe he can meet him some day. When she leaves, he tries to hack into her computer -- but sets off blaring alarms.