Andy and Terry have built their biggest treehouse yet! It has a Santa Land, a potato-powered translation transmitter, an electric pony stable, a noisy level, a Monster Mash, a wild weather dome, a gingerbread house with a nice little old lady, a gecko chamber, and a hall of funhouse mirrors. But, be REALLY, REALLY CAREFUL in the hall of funhouse mirrors. It's the perfect place to hide from Mr Bunkoff, who is trying to catch Andy, Jill and Terry and send them to SCHOOL. But their evil twins are lurking in one of the mirrors ... and they want out. Well, what are you waiting for? Come on up!.