This is the revised and updated new edition. Metallica, the seventh-biggest recording act in American history, are consummate musicians-but it wasn't always that way. A significant proportion of their playing expertise was acquired from a pivotal three-year period in their history-1983 to 1986- during which their music, a potent variant of thrash metal, evolved from garage level to sophisticated, progressive heights thanks to the teachings of their bass player, Cliff Burton.