O ne summer day in Frog Creek, Pennsylvania, a mysterious tree house appeared in the woods. It was filled with books. A boy named Jack and his sister, Annie, found the tree house and soon discovered that it was magic. They could go to any time and place in history just by pointing to a picture in one of the books. While they were gone, no time at all passed back in Frog Creek.

Jack and Annie eventually found out that the tree house belonged to Morgan le Fay, a magical librarian from the legendary realm of Camelot. They have since traveled on many adventures in the magic tree house and completed many missions for both Morgan le Fay and her friend Merlin the magician.

Now Merlin needs Jack and Annie’s help again. He wants them to travel through time and learn secrets of greatness from four people who are called great by the world. Jack and Annie have completed three of the four missions. They took a trip to ancient Macedonia, where they spent time with Alexander the Great and his war-horse, Bucephalus; they visited Coney Island in 1908, where they saw Harry Houdini and his wife, Bess, perform a magic show; and they had an adventure in Egypt in the 1800s, where they met Florence Nightingale.

Back in Frog Creek, they are waiting to see where Merlin will send them to find the fourth secret of greatness…. dI4lQ8MeISuvxg5DWSH5RyZlwp7TbkZpUD1OecqxjnFHTw2SNoaPxkRkw7RFpyNw