After the tree they called home is cut down and shipped to Los Angeles, talking chipmunks Alvin, Simon and Theodore find a new home with songwriter Dave Seville (Jason Lee). Despite a rocky start to this new arrangement, Dave eventually discovers that the spunky critters have rare singing talent. When the three perform in front of record executive Ian Hawke (David Cross), he immediately signs them. Although the infectious group rapidly gains in popularity, their loyalty is soon tested.