Corporal Marsh was a character who appeared in the Season 5 episode of the CBS-TV series M*A*S*H titled "Exorcism". The part of Dorsey was played in the episode by James Canning, who would return to appear as Captain Simmons in the Season 7 episode "The Young and the Restless".
About Cpl. Marsh & the "Spirit Post"[]
When the transport jeep carrying recently treated soldiers headed for the EVAC hospital crashes just minutes from camp, it echoes the belief of some locals that the camp is cursed with evil spirits; when some of the locals bring in a spirit post, Col. Potter initially balks at the idea; after he orders Radar to take the post away, a number of bad things happen: some light bulb goes out in OR, the gauge on the oxygen meter goes out in the middle of an operation, and then the EVAC jeep crashes, on which Marsh, who was wounded for the 2nd time in three months, and other operated on soldiers were on!
Marsh, who was getting discharged early, and was looking forward to being back stateside, has to wait still a little longer, due to serious injuries he suffered while in the jeep when it crashed; he returns to camp, in shock, as an elderly local (Phillip Ahn), steps in front of the jeep, in an attempt to ward off the "evil spirits". The second surgery on Marsh goes successful, as well as the one on the elderly man, who insisted that the staff, at the warning of his daughter Kyong Ja (Virginia Ann Lee) use a local priestess to perform an ancient Korean exorcism ritual before he's operated on. In the end, both Marsh and the other wounded soldiers who were on the EVAC jeep are successfully treated, as well the elderly Korean man, who is satisfied that the "evil spirits" were exorcised!