In a dumpster at the US Naval Academy, Annapolis, Maryland, a three-star admiral finds the body of a long-time friend, who was overdue for a meeting with him; Gibbs and company investigate. At a Trailways station Tony and Ziva pick up Tony's father, who appears to have become somehow connected with the victim in question; Gibbs questions Sr., and the two of them start on unfriendly terms; however, Sr. agrees to do a favor for the gang. Abby finds something in her lab, then something in a taxicab, then McGee finds something on the Internet, then they put it all together. Gibbs sends Ziva with Sr. on his chore, and another guest recognizes her and knows her background and status. Abby uses a connection to produce an answer and a kiss. Ziva and Sr. run into trouble, but they handle it. Jr. and Sr. talk, and they agree to do so even more.
An admiral finds the body of a long-time friend; Gibbs and company investigate. Tony and Ziva pick up Tony's father, who appears to have become connected with the victim. Sr. does a favor, and Ziva accompanies him. The gang figure it out.
- A Naval officer waits for someone, who's late. He calls the person and a phone rings in the distance. He follows it to a Dumpster where he finds the man dead inside.
Ziva comes in to work, super fired up that her US Passport came in the mail. She tries to share her joy with Tony, but he's surly because his dad called at 4:30 a.m. He hasn't called him back.
Gibbs comes in to announce the dead body of the week at the US Naval Academy in Annapolis. On the scene, the boys leave Ziva with Dumpster duty.
The man from the opening is Admiral Chase, he tells Gibbs he was waiting for Woody after getting an early morning call from him. Woody was being cryptic and told him to meet at the place they first met.
He hasn't seen Woody in two or three years. Gibbs asks Chase what his assignment is but Chase won't talk about it in the open. He says he'll be in touch.
Gibbs asks McGee to find out what Chase does at the Pentagon. A bit later, McGee reports that Chase is the deputy director of operations for the Joint Chiefs of Staff.
Back at the office, it's learn about the victim time: Woody Iverson retired as a commander from the Navy 18 years ago to join Royce Global Group, a mining and shipping company. Billionaire owner Jonathan Royce hasn't been seen in public since his son died four years ago. His daughter Rachel lives on Long Island.
McGee reports that Iverson flew in from Geneva last night with three other passengers. McGee pauses before saying who they are. He shows the security footage.
Theo Gaston, a Swiss in charge of company security; Dan Mayfied, the COO who runs things; Woody and... Tony's dad.
Tony tries and fails to reach his dad. They track his dad's cell phone to a bus station.
Gibbs meets with Dan Mayfield and Theo Gaston. They were in town for a trade symposium. They don't know where Woody went after the airport. Mayfield says Woody left with Anthony DiNozzo Sr. Mayfield says DiNozzo and Royce go way back and DiNozzo just hitched a ride on the plane.
Tony finds his dad at the bus station. He tells his dad Woody was killed. Dad is excited to see Ziva again.
Back at NCIS in interrogation, Gibbs comes to talk to Tony Sr., who says he just met Woody at the airport. Tony Sr. says he didn't talk to Woody on the plane and he hasn't seen Royce in years. He played cards the whole way with Mayfield, who invited him to the trade summit to be polite. Tony Sr. takes exception to Gibbs' tone. Tony Sr. says he and Woody shared a cab, but Woody dropped him at the Adams House.
Watching from behind the glass, Tony knows his dad is lying -- he never registered at the Adams House.
In Vance's office, Admiral Chase tells the director he's concerned Woody's death might have national security implications. He reports there was chatter among arms dealers about the trade summit. Vance tells Gibbs gaining access will be hard since it's civilian with a strict guest list.
Gibbs leaves abruptly. Downstairs, Tony Sr. is saying good bye and Jr. hustles him out. Gibbs stops him, saying they need him to get them into the reception.
Later, Tony Jr. tells Gibbs using his dad is a bad idea. And he really doesn't want his dad staying with him. Tony Sr. happily reports he booked the penthouse at the Adams House. Gibbs tells Tony Jr. they can expense it.
McGee finds what looks like a phone number with an LA area code in the notepad of Woody's phone.
Abby gets no match from the DNA Duckie found under the victim's fingernails. She broadens the search to international databases.
Abby checks Woody's coat and finds low level radiation. McGee finds the LA number is for a place that does colonics and herbal enemas.
Gibbs visits Tony Sr in the penthouse. He tells Sr. about Jr's concerns about involving him. "I think you're just enough of a con man to pull it off," Gibbs tells him.
Gibbs tells him he can cut the act, he knows he's broke. Sr. knows his son paid his hotel bill and flight to Monaco last year, making it look like a gift. Gibbs asks why all the games. Sr. says he's never lied to Jr.
Back at work, Tony Jr. is put out his dad avoided him for dinner.
McGee reports the LA area code wasn't a phone number. The 310 was the cab number, the seven digits were the DC cab company's number. Since Woody's pockets were rifled through, they wonder if what they were looking for was left in the cab. They're having the cab brought in.
Later, Abby goes over the cab. She finds a metal plaque with a serial number on it, MK 15. It's also mildly radioactive. They Google the serial number and find it belongs to a hydrogen bomb that went missing in 1956, when the plane carrying it disappeared. The bomb is 3.4 megatons, 100 times more powerful than the bomb dropped on Hiroshima.
In Vance's office, they show Admiral Chase the bomb plate. The nuclear material would have been active after years underwater.
Royce's group does a lot of underwater mining, they could have found it.
They don't want to spook Royce's people.
The team game plans for infiltrating the trade summit. Tony's really nervous about involving his dad. He says again it's a bad idea. Gibbs says an NCIS agent is going with him: Ziva.
Fred from accounting comes to tell Gibbs about the huge bill DiNozzo is wracking up.
Tony Jr. checks on his dad at the hotel, where he's being fitted for a new cashmere tuxedo -- on NCIS. His dad mixes himself a martini, and Tony realizes his dad thinks he's James Bond.
He reminds his dad his job is just to get Ziva in so she can plant a bug.
Back at the office, Duckie reports Woody was strangled. Ziva has found a law suit filed by Rachel Royce against Dan Mayfield for keeping her dad from her.
Later that night, Tony and MCGee watch surveillance .
Tony Sr. and Ziva and her giant spy camera broach enter the party.
In MTAC, they check satellite of Royce's ship in the Mediterranean. They think they're waiting for something big enough to pick the nuke off the ocean floor.
McGee and Tony run facial recognition of the party guests, including several arms dealers. The find Agah Bayar, a Turkish arms dealer on Interpol's watch list.
Bayar recognizes Ziva as Mossad head Eli David's daughter and tells Mayfield she's a federal agent. Bayar tells Mayfield he's interested in his proposition but not in spending the rest of his life in an American prison. He leaves.
Abby tells Gibbs the DNA is Theo Gaston, Royce's head of security. Gibbs radios Tony to get his dad out and tells Ziva to get an eye on Gaston. Tony Sr wants to stay and schmooze, but Ziva hustles him out -- smack into Gaston, who recognizes her as Agent David and disables her camera.
Tony and McGee race in, while Ziva takes out Gaston and Tony Sr. punches out Mayfield.
Later, they know Mayfield knew about the bomb. He's claiming he told Gaston to follow Woody, not kill him.
Swiss police found Jonathan Royce comatose on life support in his chalet, kept alive only on Mayfield's orders so he could keep running things.
Fred from accounting shows up again to report Tony Sr. is out of control, running up $9,000 in expenses. Gibbs tells him to pay it, "he's worth every penny."
Tony Sr. comes to say good-bye sporting his new NCIS cap. He says kissy good byes with Abby and Ziva.
Tony Jr. goes back to the hotel with his dad and works up to asking about his dad being broke. Tony Sr says it's not a big deal, it's happened before. He tells Tony he filed for bankruptcy when Tony was in boarding school and recovered.
Tony Jr. remembers a fishing trip when they were like a normal father and son, but assumes his dad doesn't remember. Dad takes a picture from the trip out of his wallet. Sr. says from now on they'll talk.
Tony's going to take him to the train station, but dad tells him he ran into Donald Trump and is going to hitch a ride home in style.