Gary Burghoff (born May 24, 1943) is an American actor, artist, and musician. He is probably best known for his role as Walter "Radar" O'Reilly, a company clerk that had extraordinary hearing, in the 1970 movie "M*A*S*H" and on the television series of the same name. Burghoff also has a deformed hand which was hidden on the show by special camera tricks and he held it behind his back a lot.