Andy and Terry have built their biggest and most astonishing treehouse yet! It has everything they -- and you -- could wish for, including an electric pony stable, a Santa Land, a noisy level, a kangaroo-riding range, a whatever-weather-you-want dome, a 100% edible gingerbread house and a hall of funhouse mirrors. But Anti-Andy, Terrible-Terry and Junkyard-Jill, their doppelgangers, are trapped in one of the mirrors -- and they want out.