 After Dennis meets Mr. Wilson s sister Helen and she reads the book "Treasure Island" to him and his friends Dennis decides he wants to be a pirate and dig for buried treasure, So, Mr. Wilson draws a map of his yard for Dennis and his friends to find so they can dig for where Mr. Wilson wants to plant his flowers. When Dennis and the other boys start digging they find a treasure only it came off a costume bracelet of Alice s that Henry put there for the boys to find. But, when Mr. Wilson sees it he starts getting excited until he finds out that it isn t real treasure.