Dr. Weitzman (Dennis Boutsikaris) is a psychiatrist in New York who is in charge of several patients at a mental institution. Among the members of his group are several characters. There is the mildly delusional Billy (Michael Keaton), Harry (Christopher Lloyd) who thinks he's a psychiatrist, Jack (Peter Boyle) an advertising writer who believes he hears the voice of Jesus, and Albert (Stephen Furst) the man-child bed-wetter. Feeling that his group could stand a relaxing day in the city, Dr. Weitzman takes the motley bunch to a baseball game. On the way to the game though, the patients happen to witness a crime in progress and Dr. Weitzman is attacked and put up in the hospital. Now framed for the crime and on the run from the police, the patients are stranded in New York City, and forced find a way to help the good doctor as they find out he is about to be killed by the criminals as a witness to the crime.