The boys reconstuct one of Doofenshmirtz's inventions to discover what it does after it lands in their front yard.

Phineas and Ferb try to decorate the Tri-State Area as a thank you for Santa Claus, but when Dr. Doofenshmirtz tries to spread naughtiness across the city with his "Naughty-inator," the boys must help restore holiday cheer to Danville. Meanwhile, Candace tries to find out the contents of Jeremy's wish list.