This is a knee-slapping comedy with Dan Aykroyd as a mental patient who cleverly maneuvers his way into a very profitable stint substituting for a prominent Los Angeles radio psychiatrist (Charles Grodin) while he is overseas. Lacking any built-in restraints, Aykroyd is captivating as a counselor. The public revels in his charisma and unpredictability. A fellow con man and societal outsider (Walter Matthau) sees through him but goes along for the ride. Director Michael Ritchie makes the most of the story's satirical elements. After The Couch Trip, you'll be happy as a lark.