David Sewell (Jason Lee) is a frustrated songwriter in Los Angeles. He works hard day and night, but his works are never appreciated by the boss of the record company. One day, David, who was full of anger, was furious at home. At this time, three chipmunks from the mountains, Alvin (voiced by Justin Long), Simon (voiced by Matthew Gray Gubler), and Cirdo (voiced by Jesse McCartney) broke into David's life. David was surprised to find that these three naughty little guys could not only talk, but also sing in harmony. So he reached an agreement with the little guys that they could live in his home, but they had to sing the songs written by David, and the interesting story unfolded... This film won the 2008 Children's Choice Award for Most Popular Movie.