Alvin and the Chipmunks: Back to Alvin's Future on AllMovie

Here the Chipmunks enlist the aid of Professor Clyde Crashcup who helps them travel back in time where the then-Alvin is not sure he wants to take up singing. The Chipmunks realize that they'd better talk him into his musical career, or else there won't be any Alvin & the Chipmunks at all.