What began as a crafty gimmick on 1996's Plays Metallica by Four Cellos — four classically trained cellists blasting out refined renditions of Metallica tunes — has evolved into serious business for the four Finnish dudes of Apocalyptica. Since then, the group's rock concertos have received kudos from both the heavy-metal crowd in tattered jeans and the tuxedo-donning classical set.
In addition to performing symphonic covers of hard-rock heroes such as Slayer, Black Sabbath, Pantera, and Faith No More, the foremost "cello metal" artists showcase original experimental material on the 2007 record Worlds Collide. Since trading one cellist for drummer and double bassist Mikko Sirén in 2003, the band has added even more atmosphere and bombast to its lower end.