Franklin W Dixon

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

The Hardy Boys are elated over their good luck when wealthy Elroy Jefferson invites them to spend Christmas vacation at his private retreat on Cabin Island. But when Frank and Joe make a reconnaissance trip in their iceboat, The Sea Gull to the island, a belligerent stranger orders them off. Why? Before twenty-four hours have passed, the Hardys find themselves involved in two mysteries: the first concerns the recent disappearance of Mr. Jefferson's

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Frank and Joe investigate numerous crimes in their town that may or may not be related.

When the Sweet Sixteen party plans of a local rich girl are overshadowed by pranksters who key her expensive car and post a video of the act on the Internet, Frank and Joe resolve to identify the culprits.

The Hardy brothers try to find out who is behind a rash of automobile thefts that are occurring on Shore Road just outside of Bayport.

Frank and Joe solve a mystery involving the disappearance of a professor, a hot-tempered hermit, sabotage at the new Bayport Coastal Radar Station, and the Honeycomb Caves.

The boys once again have jumped into the thick of a complicated mystery. Samuel Blacksone and his brother Ruel Rand live on adjacent properties, and it appears that one of them is out to hurt the other because they are both attacked. Frank and Joe soon learn that treasure is rumored to be hidden between the two properties, and as they investigate, they learn that others are involved in the apparent plot between the two brothers. Spooky mansions, secret...

Their SOS ignored in a storm, the Hardy boys find a wallet containing two thousand dollars alongside their boat and are launched into a mystery involving diverse clues.

A chance meeting with a stranger on the road provides the Hardy brothers with a clue to a gang of local burglars.