MGMT’s music has always pinballed between accessibility and experiment, pop, and psychedelia—a tension that has produced some of the catchiest, most synapse-stretching music of the young century. Reining in the freak-outs of 2013’s MGMT, the band’s fourth album plumbs their (relatively) accessible side, refracting ’80s-style synth-pop (“Little Dark Age,” “One Thing Left to Try”) and ’60s jangle folk (“When You Die”) through a warped, surrealistic sense of humor—a sound at once cheerful and violent, eerie and inviting, light and thrillingly dark.