A magical train ride on Christmas Eve takes a boy to the North Pole to receive a special gift from Santa Claus.

Danny twists the key of an old science fiction game. The game unleashes a localized meteor shower and wrenches Danny's house into orbit around a distant ringed planet. Besides Danny, his brother Walter and sister Lisa have to go along. Soon a defective robot, a rangy astronaut, and an alien spaceship enter the picture. The only way the kids can return their house to its proper space-time coordinates is to finish the game, but before they can finish,...