When Andy develops a severe toothache that prevents him from writing new jokes for their book, Terry uses their fantastical treehouse's money-making machine funds to purchase a Joke Writer 2000, with unexpected results.

"Andy and Terry live in a 91-story treehouse. (It used to be a 78-story treehouse, but they keep getting ideas for more stories!) ... Good thing there's so many fun things to do in the treehouse, because Andy and Terry get stuck babysitting Mr. Big Nose's three grandchildren for the day"--Back cover.

Who wouldn't want to live in a treehouse? Especially a 13-story treehouse that has a bowling alley, a see-through swimming pool, a tank full of sharks, a library full of comics, a secret underground laboratory, a games room, self-making beds, vines you can swing on, a vegetable vaporiser and a marshmallow machine that follows you around and automatically shoots your favourite flavoured marshmallows into your mouth whenever it discerns you're hungry....

"Andy and Terry are once again inviting readers to come hang out with them in their astonishing 39-story treehouse (it used to be 13 stories, then 26 stories, but they keep expanding). And this year they will have even more time to jump on the world's highest trampoline, toast marshmallows in an active volcano, swim in the chocolate waterfall, pet baby dinosaurs, and go head-to-trunk with the Trunkinator, since Terry has created the greatest invention...

Andy and Terry travel through time trying to save their treehouse from highly talented, angry ants and Inspector Bubblewrap the building inspector while rushing to meet their publisher's deadline.