 Divorcee Scott Calvin (Tim Allen) is disgusted to learn that his ex (Wendy Crewson) and her husband (Judge Reynolds) have tried - and failed - to break it easy to their 6-year-old son Charlie (Eric Lloyd) that Santa isn t real. On Christmas Eve, Scott reads The Night Before Christmas...then receives an unexpected visitor on his roof. When he s startled by Scott s calling out and falls, the Santa impersonator disappears, leaving only an 8-reindeer sleigh and a suit with instructions to put it on if he s involved in an accident. Scott does, and is transported around the town dropping gifts through chimneys until he s taken to the North Pole and informed by a group who claim they re elves that he is now Santa. Charlie is proud of his dad s new job, though Scott s convinced it s a dream. Until his hair turns white, his beard refuses to stay shaved, he gains weight inexplicably, even for his sudden love of junk food...Now he s accepted it, there s just one problem: how to keep it secret from his disbelieving family?