After a dying criminal confesses that his loot has been stashed "in the tower," the Hardy boys make an astonishing discovery.

Each of five children lucky enough to discover an entry ticket into Mr. Willy Wonka's mysterious chocolate factory takes advantage of the situation in his own way.

Fenton Hardy, the famous private detective and father of the Hardy Boys, asks his sons to help him with his latest case involving the illegal drug trade. Hardy sends Frank and Joe to a house on the cliff, whose location offers an excellent vantage point to watch for smugglers. The Hardy Boys are tricked into going inside the house by cries for help and find themselves trapped for a short time in the attic, meanwhile, their telescope and motorcycles...