System of a Down makes thinking-man's metal on Mezmerize (the first of a two-part opus that will be followed by Hypnotize later this year), which opened at No. 1 on the Billboard pop albums chart. On the tempo-shifting single "B.Y.O.B.," that last B cleverly refers to both beer and bombs; it juxtaposes images of "dancing in the desert" with a tirade against war. Not your usual head-bangers, System has a more artful approach that sometimes suggests rock opera. And on the closing ballad, "Lost in Hollywood," the L.A. quartet shows its melodic mettle.
DOWNLOAD THIS: "B.Y.O.B."