The youngest child of the family often has the most problems - so why should things be different for the Prince of Darkness and his offspring? Satan is considering retirement, and is pondering which of his sons should take over the family business - ambitious Adrian, strapping Cassius, or Nicky, an accident-prone demon who prefers to stay in his room playing his favorite heavy metal tunes. When Satan decides to stay on for another 10,000 years, Adrian is outraged, and leaves Hell to go to New York, where he and Cassius attempt to round up enough souls to vote Satan out of power. Satan, understandably upset, sends Nicky to bring Adrian and Cassius back home, but Nicky finds life on Earth is more complicated than he expected. Things don't get any easier when he develops a crush on Valerie, a good-hearted mortal woman.