Rooftop clatter leads to merry adventure after Santa falls down on the job, and Scott Calvin's son Charlie convinces dad to try on the red suit. Eight reindeer pilot the pair to the North Pole, where they discover that donning the famous suit, dad must now accept all of Santa's duties. Over the next year, a surprised, not so jolly Scott grows a Santa sized tummy and beard, causing friends, family and business associates to wonder if he's lost his marbles. All except Charlie, who thinks his dad is perfectly suited for his new job!