Mutations is Beck's most melodious and accessible album. None of the songs explore new territory, but they're rich, lyrically and musically. There's an off-the-cuff wit to the songwriting, especially on Canceled Check and Bottle of Blues, and the performances are natural, relaxed, and laid-back, without ever sounding complacent. In fact, one of the nifty tricks of Mutations is how it sounds simple upon the first listen, then reveals more psychedelic layers upon each play. In its own quiet, organic way, Mutations is as great as Mellow Gold or Odelay.