Hawkeye and Trapper operate on a famous Colonel - after discovering that he is particularly ruthless about sacrificing his men, they come up with a scheme to get him sent back to the states with a little unwitting help from Frank, Margaret, and a drunk Henry.

Once again, Hawkeye writes home to his father, telling him of the latest gossip: the camp gets a new surgeon, who turns out to be a fake; Hawkeye bets he can walk into the mess tent naked for lunch, and no one will notice; Radar cheats on his final exam from the High School diploma company; Margaret rejects Franks advances and he gets drunk late into the night; the camp have a no talent night.

Captain Kaplan is to be shipped home, but becomes paranoid that something will happen to him before he leaves. He takes the wheel of the jeep to drive to Kimpo himself, but crashes and ends up in plaster. Henry's wife is in labor and gives birth while he has Radar calling the hospital every 5 mins.An entertainer, Jackie Flash, visits the camp to entertain the troops.

Brought on by Frank and Margaret's negative reports, General Clayton assigns a psychiatrist, Captain Hildebrand, to examine the 4077th M*A*S*H unit, to see if it should be disbanded. Henry tells them to be on their best behavior, or else they will be split up. But the 4077th soon begins to act in their traditional, insane ways: the shrink experiences Max Klinger, watches the hijinks of Hawkeye and Trapper John, and witnesses the trysts of Frank and Hot Lips. While Hildebrand confronts the unit on its behaviour, choppers bearing wounded begin to arrive and everyone heads for the OR. The onslaught of casualties shows the 4077th's true side.

Radar writes the weekly activity report. Hawkeye operates on a wounded prisoner who grabs a scalpel and attacks the doctors. Frank wants Klinger thrown out on a section 8,so Henry calls in a psychiatrist, Major Freedman. Hawkeye is attracted to a new nurse but thinks she is married. Trapper loses a patient who developed complications during the O.R. fracas with the wounded soldier.

Hawkeye and Trapper want the army to admit responsibility for the accidental bombing of a local village. They fill out a report and Major Stoner arrives to investigate, and leaves with all the evidence. When the story is released it claims that the enemy bombed the village, and the army tries to gag the doctors. But, thinking there could be a medal in it for him, Frank has also put a report together, with copies of all the evidence, including shell fragments, so the army comes clean.

Hawkeye has been in non-stop surgery for 3 straight days without sleep, and the wounded keep coming. He decides to find out who started the war, and sends a telegram to Harry S Truman. After listening to some of Frank's rubbish about the North Koreans wanting better plumbing, he tries to send the officers' latrine to the North Koreans with an offer of peace. Trapper finally manages to sedate him. Trapper (about Hawkeye): "I guess he's just unstable. You see, he took this weird oath as a young man, never to just stand by and watch people die."

A lone sniper has the 4077th pinned down - including Radar and Henry in the shower. The poor boy thinks he's firing on McArthur's headquarters, and a chopper finally comes by and wounds him with gunfire from above, ending the siege. Hawkeye walks out to into the bush to tend to the wounded soldier.

The camp succumbs to the Asian flu, except for Hawkeye and Margaret, who have to do everything themselves. As the others start to recover, Hawkeye falls ill but he still manages to operate when wounded arrive. Finally the others are well enough for Hawkeye to stop working and rest. He is thanked for his service with a commemorative roll of toilet paper.

Hawkeye and Trapper recover from an all night party. Henry gets a barbecue, and Hawkeye puts in a request for an incubator. The Quartermaster turns him down. They locate a Major with 3 incubators, but he won't let them have one. A Colonel tries to sell them one, and then they get into trouble with a General at a press conference. Finally, Radar trades the barbecue for an incubator.

Hot Lips gets depressed and requests a transfer, causing turmoil in the camp.

Klinger pretends to be pregnant. Hawkeye and Trapper operate on General Mitchell's son, and the General gives them 3 days in Tokyo Henry keeps getting calls from Tokyo about what Hawkeye and Trapper are doing. When they get back to the 4077 Frank asked the general for an officers club for the camp. They plot to allow the enlisted men access to the club, and when the General opens it the rules are bent to give his son access, which Hawkeye exploits to give access to all.

A Korean family set up camp in the middle of the compound. A Korean woman with a baby comes looking for the father, and names Radar. Civilian affairs relocates the family and blood tests prove Radar is not the father.