Although the concept for this animated film is derived from the adult fantasy magazine of the same name, HEAVY METAL is clearly targeted for a teen audience. Divided into a number of episodes, the film is held together by the Loc-Nar, a sinister, glowing jewel that catapults characters into weird, threatening confrontations. In one of the better episodes, a New York City cab driver becomes involved with a sexy but greedy woman who is being chased by criminals. In another, a young bookworm (voiced by John Candy) is transformed into a brawny, heroic stud and saves a maiden from being sacrificed to the jewel. Otherwise, it's a mixed bag, but successful in a mindless, adolescent way. The spirited, energetic music is contributed by a variety of rock performers, including Blue Oyster Cult, Black Sabbath and Nazareth.