He was portrayed by Robert Symonds.
A medical doctor, Baldwin was an administrator at Tokyo General Hospital, a US facility for treating wounded soldiers. When Colonel Potter of the 4077 MASH needed a surgeon on a fill in basis to replace the AWOL Major Frank Burns, Baldwin - still smarting from owing a large amount of money to Major Charles Emerson Winchester III after being defeated at cribbage - decided to send Winchester to the 4077 for 48 hours. When Burns was finally arrested and sent stateside Baldwin decided to make the transfer permanent as a way of getting out of his debt to Winchester.
Some time later Baldwin decided to visit the 4077. Winchester decided to try to butter up Baldwin in the hopes that Baldwin would transfer him back to Tokyo. Playing cribbage with him Winchester threw the games so that Baldwin would win back the money he lost to Winchester. When Winchester tries to talk Tokyo with Baldwin the Colonel then asked Winchester to find him some female companionship. Despite his disgust Winchester arranged for a call girl to visit Baldwin.
When head nurse Margaret Houlihan checked up on Baldwin he tried to rape her, and was injured when she fought him off. Meanwhile the call girl thought she had been set up by Winchester and had her enforcer confront him. He coughed up the money to keep the enforcer from breaking his legs. Meanwhile Houlihan also confronted Winchester over what had happened, then left to get Col. Potter.
It was then that Baldwin told Winchester that he was going to accuse Houlihan of coming on to him, and that if Winchester backed him up he would arrange for Winchester to be transferred back to Tokyo. When Col Potter arrived demanding answers Baldwin did as he planned and accused Houlihan of coming on to him. However Winchester had enough of Baldwin and refused to cover for the man, telling Potter and the others that Baldwin was lying through his teeth and that he would not destroy Houlihan's career even though it meant having to stay at the 4077.
Realizing that Potter and the rest of the camp believed Winchester, Baldwin high tailed it out of camp in a jeep before Potter could have him arrested.