A struggling songwriter named Dave Seville finds success when he comes across a trio of singing chipmunks: mischievous leader Alvin, brainy Simon, and chubby, impressionable Theodore.
Pop sensations Alvin, Simon and Theodore end up in the care of Dave Seville's twenty-something nephew Toby. The boys must put aside music super stardom to return to school, and are tasked with saving the school's music program by winning the $25,000 prize in a battle of the bands. But the Chipmunks unexpectedly meet their match in three singing chipmunks known as The Chipettes - Brittany, Eleanor and Jeanette. Romantic and musical sparks are ignited when the Chipmunks and Chipettes square off.
Through a series of misunderstandings, Alvin, Simon and Theodore come to believe that Dave is going to propose to his new girlfriend in New York City - and dump them. They have three days to get to him and stop the proposal.
Playing around while aboard a cruise ship, the Chipmunks and Chipettes accidentally go overboard and end up marooned in a tropical paradise. They discover their new turf is not as deserted as it seems.
The Chipmunks and the Chipettes go head to head in a hot air balloon race, and the winner gets $10,000. Unbeknownst to the participants, the "race" is actually a diamond smuggling ring!
While the Chipmunks are working at the amusement park, Majestic Movie Studios, in a singing attraction. Little do they know that the real Dr. Frankenstein are in a new attraction called, "Frankenstein's Castle". After Alvin drives a crazy bus ride, they miss their next performance and get locked in the park after closing time. Dr. Frankenstein figures that the castle isn't scary enough and re-creates the real Frankenstein and after the monster finds the boys, it starts a wild and wacky adventure!
As Alvin struggles with nightmares involving werewolves, the school play of Jekyll & Hyde is in jeopardy when the lead, Alvin, is suspended. In an attempt to boost his confidence, the drama teacher suggests Theodore, who's suddenly going through some canine changes.
A live-action/animated TV special featuring Alvin and the Chipmunks.
Alvin learns the true meaning of Christmas.
The Chipmunks are discussing when they were born and began to argue. They wanted to go and find their mother but Dave doesn't let them. The Chipettes are invited round while the Chipmunks go and look for their mother but Dave finds out and gets worried...
When he hears that the original Easter Bunny was not a rabbit at all, Alvin becomes convinced that the first deliverer of Easter baskets was indeed his grandfather, the Easter Chipmunk.
Thanksgiving Day is on the way.
Alvin, Simon, and Theodore finish making invitations to send to their relatives and then leave to audition for the town play "Pilgrims Adventures in a New Land". Alvin trys for the role of the Lead, while Simon trys for Lighting and Sound director, and Theodore Costume Designer. However, the Director of the play feels that to properly celebrate the pilgrims story of adventure, the boys should branch out and attempt new positions. As a result, she casts Simon as the Lead, Theodore as Lighting and Sound Director, and Alvin as the Costume Designer to expand their talents.