B.J. and Hawkeye try to get a hardship discharge for an immigrant Marine whose Mom is being deported before he can get home. Winchester becomes C.O. for a few days, using his new position to get himself silk sheets and other "basic necessities of life".
Klinger happens upon a bottle of vintage French wine and Hawkeye uses it to lure a nurse into his clutches. Winchester deals with Klinger to get more bottles of the wine. Col. Potter trades with the Canadians for a special anesthetic forbidden by the U.S. Army.
When the steam generator explodes in O.R., Klinger pushes Charles out of the line of fire just in time, but B.J. catches part of the blast and has a serious arm injury. For saving his life, Charles declares he is fully indebted to Maxwell Klinger and becomes his personal assistant. But after several days of bowing to Klinger's ever command, Charles begins to wish he HAD been killed. Meanwhile, Hawkeye doesn't like the doctor called in to help treat B.J., who refuses to admit there is anything wrong with him.
We're having a heat wave! The 4077th deals with a sudden heat wave in their own personal ways: Klinger disassembles the P.A. system, Charles goes through all of his tax returns and bonds, B.J. stresses over a letter from Peg, Margaret develops a severe case of prickly heat, and Colonel Potter can't get a good night's sleep.
When Winchester goes to inspect the sanitary conditions at another camp, the failing mark he gives the commander is met with physical violence. Meanwhile, the gang comes up with a surprise for B.J. on his anniversary.
Margaret's good friend Captain Helen Whitfield visits the 4077th and it seems like old times again, but what the Major doesn't know is that Whitfield is still a raging closet-alcoholic; Meanwhile, Hawkeye pulls one prank that goes too far when he drops Charles' pants in O.R.
Col. Potter's blood pressure is too high and he has two weeks to get it back down, causing everyone to mollycoddle him, much to his dismay. Meanwhile, the malaria medicine they are sent makes Klinger sick.
Father Mulcahy tries to prepare himself and the camp for a visit from Cardinal Reardon, a VIP to both the Army and the church. Hawkeye, meanwhile, prepares to tell a young soldier why he can't donate blood to his wounded buddy; Hawkeye and B.J. have discovered the soldier has leukemia.
Klinger accidentally breaks Potter's eyeglasses, requiring a visit from traveling optometrist Dr. Bud Herzog. The 4077th receives fresh vegetables from a grateful Korean. Potter questions the authenticity of an upbeat letter from Radar.
Father Mulcahy counsels a guilt-ridden GI who swapped tags with a dead colleague. B.J. and Charles consider ways of keeping a soldier-salesman quiet, while Hawkeye and Margaret help another GI get even with the woman who jilted him.
The Army is starting a new MASH unit, and the surgeons and staff of the 4077th fear they will be split up and reassigned. So they act completely unprofessional, uncouth, and incompetent in front of an army rep hoping he will reconsider.
It's the day of Klinger's hearing before a trial of angry officers. Will Klinger be sent up the river? With Charles as his attorney, it's almost certain. Meanwhile, Hawkeye and B.J. set out to catch the real thief.