The magic tree house takes Jack and Annie to a moon base in the future where they continue to search for the fourth thing they need to free their friend Morgan from the magician's spell.
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.
Their magic tree house takes Jack and Annie back to retrieve a lost story in ancient Greece, where they witness the original Olympic games and are surprised to find what girls of the time were not allowed to do.
Eight-year-old Jack and his younger sister Annie use the magic tree house to travel back to the Middle Ages, where they explore a castle and are helped by a mysterious knight.
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.