The Treehouse is where George & Harold Meet up & do their comics in their pastime, It was first made by George's dad to play in every now and then.
The Adventures Of Captain Underpants
The Wrath Of The Wicked Wegie Women
The boys have a sleepover under George's Dad's conditions but they are eventually captured by the hypnotised Ms. Ribble.
Preposterous Plight of the Purple Potty People
In the alternative universe, it has become the coolest treehouse on the Earth due to all the stealing & crime committed by Captain Blunderpants.
Terrifying Re-turn of Tippy Tinkletrousers
We see the time in George & Harold's kinder years when the treehouse was first being built with space, heater, Tv & random essentials.