A wish-granting comet is headed to Middleton. The residents are all excited to go to the observatory to watch it as it only occurs once every 100 years. Nick and Grace get nostalgic as they deal with the last few days of high school. Adam and Stephanie are over the moon with glowing reviews of their food truck while Abigail is heartbroken over Donovan and decides to take a trip to Europe to get way from everything.
As the Christmas season approaches, Dan Ryebeck (Ethan Erickson) is facing unemployment, and struggling to pay for the gifts he thinks will impress his two kids, Sally (Annie Thurman) and Joe (Griffin Cleveland). Always chasing a new business idea, Dan hasn't had time for family, including his wife Linda (Anne Dudek), who is finally fed up and filing divorce papers. Threatened by Linda's handsome and successful young boss, Trevor (Steve Valentine), Dan knows he must make this Christmas the best one yet to win his family back. But after auditioning for a mall Santa job and quickly losing his cool, Dan is frustrated and broke, blaming the holidays for his troubles. Little does he know his luck is about to turn around when the real Kris Kringle (Donovan Scott) pays him a visit from the North Pole. Deciding to take a vacation and leave Dan in charge, Kris sends his hard-working elf assistant Eddie (Sean Astin) to guide Dan as the new Santa Claus, hoping he'll learn a lesson in Christmas spirit. With the sudden power to impress Linda and the kids by making every wild Christmas wish come true, Dan soon gets carried away. As the fate of the whole world's Christmas rests in his hands, can Dan focus on what his family really needs without flubbing his greatest gig yet?