Alvin, Simon, and Theodore are back in director Tim Hill's computer-animation/live-action hybrid following the further adventures of the world's most adorable singing trio. Songwriter Dave Seville (Jason Lee) has been struggling to gain recognition in the music industry for some time, and despite the fact that his former college roommate (David Cross) is now a high-profile powerbroker at Jett Records, Dave still can't manage to get a break. Things soon start to look up, however, when Dave discovers three singing chipmunks hiding out in the branches of a Christmas tree in Jett Records' world headquarters. Realizing that these woodland crooners cold prove to be his ticket to the big time, Dave does his best to transform Alvin (Justin Long), Simon (Matthew Gray Gubler), and Theodore (Jesse McCartney) into the next great pop sensation. As adorable and talented as they may be, though, these bouncy little critters aren't quite domesticated just yet; they still have a wild streak in them a mile wide, and it isn't long before Dave's life, home, and career are in utter chaos. But staying mad at such lovable little creatures is next to impossible, no matter what kind of mischief they might get into.