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.