The Aldens are visiting Grandfathers friend Amy at the Ogopogo Retreat inCanada. Amy rents cabins to tourists who hope to see the mysterious underwatercreature ... » 

The Aldens are visiting Grandfathers friend Amy at the Ogopogo Retreat inCanada. Amy rents cabins to tourists who hope to see the mysterious underwatercreature the Ogopogo swimming in Lake Okanagan. Henry Jessie Violet andBenny cant wait to try and spot the Ogopogo from their cabin. Amy tells thechildren about a riddle that an old friend left for her in one of the cabinsthat could lead to a small treasure. The children need to find the treasureand fastotherwise Amy will have to sell the retreat. As the riddle starts tounfold strange things start to happen around the lake. Something is movingaround in the water late at night and someone doesnt want the Aldens helpingAmy. Will the Boxcar Children crack the riddle before its too late? «