Their magic tree house takes Jack and Annie back to a monastery in medieval Ireland, where they try to retrieve a lost book while being menaced by Viking raiders.
Jack and his younger sister take a trip in their tree house back to ancient Egypt, where they help a queen's mummy continue her voyage to the Next Life.
On Christmas Eve, Jack and Annie's tree house transports them to King Arthur's castle at Camelot, where they undertake a quest to the castle of the Otherworld.
The magic tree house takes Jack and Annie to Africa where they meet up with wonderful wild animals, a very hungry warrior, and where they even solve a riddle.
Their magic tree house takes Annie and Jack to Pompeii just as Vesuvius is about to erupt, and they must find a Roman scroll before everything is covered with burning ash.
Their magic tree house takes Jack and Annie deep into the sea, where they meet up with dolphins, sharks, and octopi as they search for the answer to an ancient riddle.
Eight-year-old Jack and his younger sister Annie use the magic treehouse to travel back to the Middle Ages, where they explore a castle and are helped by a mysterious knight.
Andy and Terry recount the story of how they first met and decided to build a twenty-six story treehouse, which includes an ice cream parlor, a rink for bumper cars, and the Maze of Doom.
In their magic treehouse, Jack and Annie are again transported to King Arthur's realm, where invisible beings, giant ravens, and mistaken magic spells have a duke's castle in an uproar on Halloween night.
When Jack and Annie travel back to the Kansas prairie in search of "something to learn, " they gain an understanding of how hard life was for pioneers and they experience the terror of a tornado.
Continuing their efforts in the ever-expanding treehouse, Andy and Terry tackle the mystery of their missing publisher, Mr. Bignose, whose disappearance has made completing their next book rather difficult.
Andy and Terry try to meet a latest book deadline despite distractions in their sophisticated tree house home, including flying cats, giant bananas, and sea monsters pretending to be mermaids.
When their over-the-top ideas expand their amazing treehouse to include a giant submarine sandwich shop and a human pinball machine, Andy and Terry find themselves babysitting Mr. Big Nose's three troublesome grandkids.