Mental patient John Burns is more sane than even his doctors suspect. At least on his good days. A prominent psychiatrist with a radio talk show in Los Angeles needs a short-term replacement and looks to Burns' doctor. On the phone he unknowingly speaks with Burns instead, who books himself as the replacement host. Once on the air, Burns dispenses surprisingly good advice, but he also pushes the limits of what is considered decent on the radio. Before his escapades are discovered, Burns has helped a lot of people and even joined his listeners for a baseball game. The regular host will not, however, allow Burns' exploits to go unpunished.