The Dream Team (1989)

Dr. Weitzman works with patients in a sanitarium. Convinced that all that his "group" needs is a some fresh air and some time away from the sanitarium, he persuades the administration to allow him to take them to a ballgame. Unfortunately, he accidentally stumbles across a crime in progress and ends up in hospital. The group is stranded in New York City, forced to cope with a place which is often more bizarre than their sanitarium.