Magically transported to southwest China to find the final object needed to break the spell on the wizard Merlin's beloved penguin, Jack and Annie take a side trip to the world's largest giant panda reserve.
Jack and Annie travel to Vienna, Austria, in 1762 where they meet the young Wolfgang Amadeus Mozart and his sister and help save the budding genius' life.
Jack and Annie travel to a monastery in the Swiss Alps where, with the help of St. Bernard dogs and magic, they seek the second of four special objects necessary to break the spell on the wizard Merlin's beloved penguin, Penny.
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.
Having used their magic tree house to travel to India, where they must get a gift to help free the dog Teddy from a spell, Jack and Annie have adventures involving a tiger and other endangered jungle animals.
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.
Using their magic tree house, Jack and Annie travel back to the time of the American Revolution and help General George Washington during his famous crossing of the Delaware River.
Jack and Annie travel in their magic tree house to Elizabethan London, where they become actors in a production of A Midsummer Night's Dream and try to rescue a tame bear.
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.
The magic treehouse takes Jack and Annie back two thousand years to ancient China where they must find the original copy of an old legend before the Imperial Library is burned down by the evil Dragon King.
Eight-year-old Jack, his seven-year-old sister, Annie, and Peanut the mouse ride in a tree house to the Amazon rain forests, where they encounter giant ants, flesh-eating piranhas, hungry crocodiles, and wild jaguars.