Jack and Annie travel back to nineteenth-century Ireland to inspire a young Augusta Gregory to share her love of Irish legends and folktales with the world.
As a thank-you from Merlin and Morgan, Jack and Annie are sent on what should be a vacation at a luxurious resort in Cozumel, Mexico, but is, by mistake, an adventure with ancient Mayans, instead.
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.
Jack and Annie are in for an exciting, scary, and sad adventure when the Magic Tree House whisks them back to the decks of the Titanic. Is there anything they can do to help the ill-fated ship? Will they be able to save anyone? Will they be able to save themselves?