Heavy metal group After almost 30 years, a dozen albums, and a slew of Grammy Awards, Metallica has more than proven its staying power as rock's preeminent metal group. The group paid its dues during the hair band era of the 1980s, but Metallica's self-titled 1991 release addressed the decidedly adult topics of nuclear holocaust, mental illness, suicide, and the dangers of drug addiction. Yet despite these grim themes, Metallica's music runs contrary