Nippon Nancy – The Japanese propaganda broadcaster – Seems to have a source of inside information on the Taratupa base, and especially on Captain Binghamton. Binghamton is convinced that there is an informant, somewhere on the base, and suspects one of McHale's men. But, in a meeting, in Binghamton's office, McHale angrily informs The Captain that his men – Though they may not be 'spit-and-polish' Sailors – Are all "True, blue Americans".
Binghamton then asks McHale if some of the natives who visit his island, now and then, might have a bit of Japanese blood in them, and suggests that they might be the ones who are leaking information to the enemy. And, in the midst of telling the Captain that there isn't a drop of Japanese blood within 500 miles of his base, he suddenly pauses, when he remembers Fuji.
Binghamton can tell that McHale has something on his mind. He tells McHale that this situation has him stressed out, and that his blood pressure has risen to 174, and demands an answer from McHale. But McHale doesn't let on, and, before he leaves, he promises to do a thorough security check of his island.
Later, on McHale's island, The Boys are discussing the possibility that Fuji might be the informant. It's hard for them to believe that their good friend might be passing information to the enemy, but they can't dismiss the possibility. McHale and the guys all agree that Fuji is a great guy, but McHale suggests that they keep their eye on him, just the same.
Later, in his office, Binghamton is composing a letter to 'Pumpkin' (His Wife), detailing his day-to-day experiences, when he takes a break to listen to Nippon Nancy's latest broadcast. Carpenter enters, and joins Binghamton for the broadcast, during which, Nancy again mentions Binghamton's name.
"A man whose blood pressure is one hundred seventy four…" says Nancy, "…Should learn to take things easier."
This stresses Binghamton out even more, and, in the midst of his ranting and raving about the pressures of a combat command, his phone rings.
Admiral Reynolds is on the other end, and, having heard Nancy's broadcast, angrily presses Binghamton for an answer as to how the Japs know such personal information. Binghamton tells The Admiral that they're looking in to the situation, and Reynolds tells him to 'Get the lead out'.
Once off the phone, Binghamton and Carpenter puzzle over how such information could have leaked out. Then, Binghamton suddenly remembers having told McHale, earlier that his blood pressure was 174. He's convinced, now, that McHale is the traitor, but he needs a way to infiltrate the McHale organization for hard proof. Carpenter suggests bringing in an Agent from G-2 (Naval Counter-Espionage), but Binghamton knows that McHale would be immediately suspicious of a new face, on the island. He knows that his spy should be someone they would never suspect, and Binghamton pauses, when the name 'Parker' comes to mind.
Later, Parker reports Binghamton's office, Binghamton gives Parker a choice. Either he'll receive a citation… Or face a firing squad. Parker, of course, must give in, and agrees to help Binghamton, but balks, when Binghamton reveals that it's McHale and his Crew that he'll be spying on. Parker defends McHale, adding that he's a "Staunch Patriot", but Binghamton – Again, with the threat of a firing squad – Convinces Parker that he should go along with the plan.
Later, on McHale's island, Parker goes to work. After doing a bit of snooping around, outside, he steps into McHale's hut, and begins to look around. He goes to a cabinet, opens a drawer, and finds a calendar, with a picture of a pretty Japanese girl. Just as he begins to look the picture over, McHale happens in, and catches him.
McHale doesn't recognize Parker, at first, in his civvies, but, when he sees who it is, he asks Parker what he's doing. Before Parker can stutter out an answer, McHale sees the calendar.
"Uhh huh-huhh!" says McHale, with a smile, as he takes the calendar from Parker. "So that's it, huh?"
"That's what?" asks Parker, nervously.
"You rascal!" says McHale, still with a smile. "You were sneakin' in here to take a look at Miss Wild Rice, huh?"
"Miss who?" asks Parker.
"Miyoshi Yakamuri" reads McHale, from the calendar. "Miss Wild Rice of nineteen thirty eight. Says so, right there."
Parker quickly becomes a bit suspicious, with the fact that McHale can read Japanese. McHale goes on to tell Parker that he learned Japanese during his many visits to the port of Yokohama, on the merchant ship he served on, before the war.
But then, McHale becomes suspicious, himself, and asks Parker what's going on. But Parker plays dumb.
McHale then notices a bulge at Parker's belt-line and asks about it. Parker answers that it's nothing, then McHale shouts for him to suck in his gut. When he does, the gun he has stuffed into his waistband goes off, causing them both to duck, and run for cover.
McHale then steps over, bends, and picks up the .45 automatic that fell from Chuck's pants. He asks Parker what he was doing with the gun, and, before Parker can stutter out an answer, the guys, rush in, having heard the shot, and ask what's going on. McHale calms the guys down, and presses Parker for an answer about his suspicious behavior.
Parker spills the beans about how Binghamton had ordered him to spy on his own Crew. The Boys aren't very happy about it, but McHale sends them away.
Later, Parker, having changed back into his uniform, is alone in the hut, when he hears a noise, outside. He quietly steps toward the window, and hides, beside it, as Captain Binghamton slowly rises, and peeks through the window. Parker makes his presence known, and Binghamton asks him where McHale was, the last time Parker saw him. Parker tells him that McHale was headed out into the jungle, and Binghamton suggests that he might be going to rendezvous with an enemy submarine. Parker tries to explain why McHale went to the jungle, but Binghamton cuts him off, and orders Parker to accompany him into the jungle, to look for McHale.
Later, after they've searched for a while, Parker and Binghamton step into a clearing. Parker soon spots McHale, on the beach, talking to Fuji, who is in swim trunks, holding a large, black box.
Parker tries to keep Binghamton from seeing the two, by holding a brush limb in front of his face, but isn't successful. Binghamton spots them, and Parker pretends not to see them, in the hope of convincing Binghamton that he's having a hallucination. But, it doesn't work, and Binghamton orders Parker to stay put, while he heads out to get help.
When Binghamton is out of sight, Parker rushes over, and tells McHale and Fuji about Binghamton's having spotted them. McHale asks where Binghamton went, and Parker answers that he was headed for the main base. Parker then asks what McHale and Fuji were up to, but McHale puts Parker off, and they all head out.
Soon, Binghamton arrives at his office, rushes to his desk, and gets his .45 out. Carpenter soon rushes in, with the news that Admiral Reynolds has been trying to contact Binghamton. It seems that Reynolds is coming to Taratupa to discuss an urgent matter, but Binghamton won't listen. He orders Carpenter to reach the Officer Of The Deck, and have a contingent of Marine Guards, fully armed, and ready to shove off, in 5 minutes.
"If the Admiral wants me…" says Binghamton, as he heads for the door, "I'll be over at McHale's island!"
Binghamton pauses, at the door, and steps back to Carpenter.
"Breaking up a spy ring!"
Binghamton then rushes out the door.
Shortly later, at the dock, on McHale's island, Fuji is about to shove off, in a canoe. Fuji wants to know why he can't just hide in the hills, as usual, but McHale explains that Binghamton will probably go over the island with a fine-toothed comb, and they can't afford to take chances on Fuji's being found.
Then, The Boys rush over with a report on Binghamton's approach, along with a boatload of Marines. McHale orders the guys to stash the canoe, then, with no other option, on such short notice, McHale stashes Fuji in a fuel drum, and puts the lid on.
Binghamton and the Marines soon arrive, and Binghamton orders them to place McHale and his Crew under arrest. The Marines rush McHale and Parker, and, as Binghamton steps to McHale, McHale – Standing behind the fuel drum, which contains their Japanese friend – Calmly asks what the big fuss is all about. Binghamton angrily returns that McHale and his bunch are about to have their necks stretched, for high treason, and orders the Marines to search the island.
Just then, Carpenter arrives, in a motor launch, with 2 armed Sailors. Binghamton steps over, and tells Carpenter that he doesn't need any help with the search, and adds that he intends to nail McHale and his men by himself. Binghamton notices that Carpenter looks a bit sad, and asks what's wrong, and Carpenter sadly informs The Captain that he's under arrest.
Binghamton, of course, doesn't take the news well, and Carpenter goes on to say that Admiral Reynolds had called, on the scramble phone, and ordered Binghamton's arrest, on a charge of Suspicion Of Espionage. Carpenter then reluctantly orders the Sailors to take Binghamton away, but Binghamton doesn't go quietly.
Later, in Binghamton's office, with McHale present, Binghamton frantically pleads his case, to Admiral Reynolds. However, it's not necessary, for Reynolds relates the news that he's just received a report from San Diego that Binghamton has been cleared of all charges. Relieved, Binghamton then orders McHale to tell Reynolds about his meeting with the 'Japanese Agent', in the jungle, earlier. But Reynolds finds it ludicrous that McHale would be involved with any espionage activities.
"If the Japanese aren't getting their information from him…" says Binghamton, indicating McHale, "Who are they getting it from?!"
"Your Wife!" returns Reynolds, sternly.
"Pumpkin?" asks Binghamton, surprised.
"Pumpkin?" repeats McHale, just as surprised, then: "I mean, his Wife?!"
Reynolds shows Binghamton photostats of his letters to 'Pumpkin', which he's received from San Diego. After he reads some examples, Reynolds explains that Mrs. Binghamton had dined at a San Diego restaurant, and related, to friends, details of her Husband's health, including his indigestion, and his blood pressure. Japanese spies had heard the information, and related it home, where it was used by Nippon Nancy.
After Binghamton complains about his big-mouthed Wife, Reynolds leaves.
Later, in his office, Binghamton admits to McHale that his nerves are shot, but must know, for his own peace of mind, whether or not he was hallucinating, earlier. He asks McHale, straight-out, whether or not he was on the beach, earlier. McHale answers, truthfully, that he was. Then, Binghamton asks McHale if he had been alone, on the beach, earlier.
"Are you sure you want me to answer that, sir?" asks McHale.
Binghamton thinks for a moment, then answers:
"No. No… We'll just forget it."
McHale quietly excuses himself, and, as he McHale turns to leave, Binghamton stares at the photo of his 'Pumpkin', on his desk.
"Ohh, yap, yap, yap, yap, yap, yap, yap!!" he says, angrily, then, frustratedly…
"I could just scream."