The Chipmunks and The Chipettes go on a cruise trip with their manager/father figure, Dave Seville (Jason Lee) aboard the Carnival Dream cruise ship. During the cruise, the 'Munks and 'Ettes turn the ship into their personal playground, causing trouble and running amuck as they will. Eventually, their chaotic behavior gets them ship wrecked on a desert island, everyone getting lost in the process. As Dave sets out to look for the lost chipmunk trios, the six find a new castaway named Zoe (Jenny Slate) on the island who turns out to be more than a match for the trios.