BOOK FOUR: Orvie visits an isolated island in the southern section of Lake Michigan, intrigued by rumors of a ghost ship that sails in close to shore, fires volleys of cannon balls at the island and then turns and disappears into thin air. He befriends the twelve year old nephew of the owner of the Hotel on the island - Windsor Island - and the two boys work to solve the mystery of the ship and discover who is behind an attempt to buy all the property...