An idealistic but struggling actor finds his life unexpectedly complicated when he stops a robbery while wearing the costume of Captain Avenger, a superhero character of a film he is hired to to promote. He decides to dabble at being a superhero only to find that it is more difficult and dangerous than he ever imagined.

A mentally unstable Vietnam War veteran works as a night-time taxi driver in New York City where the perceived decadence and sleaze feed his urge for violent action.