Frank and Joe are up against some jewel thieves when their detective father asks them to retrieve a top-secret invention from the home of their scientist neighbor.

The Hardy boys find the missing deed to an Indians' land, prevent a phony salesman from carrying through a reckless scheme, and help their father solve a top-secret case.

When their peregrine falcon brings down a homing pigeon carrying rubies, the Hardy brothers find themselves involved with kidnappers.

The Hardy boys help out when a magicians' tournament is threatened by mysterious happenings.

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...

The Hardy boys investigate a scream that they feel belongs to someone in trouble.

In the Northwest Territories of Canada, the Hardy brothers and Chet Morton help to recover a stolen Viking relic.

Who or what is the Aztec warrior, and where should they begin theto search for him? The boys' quest for the snawer takes them to the ancient ruined temples of Mexico - and into a lethal trap.

Valuable electronic parts containing platinum are being stolen from shipments made by Stanwide Mining Equipment Company's cargo planes and Frank and Joe Hardy are called upon to assist their world-renowned detective father solve the baffling case. At Stanwide, the boys pose as employees and become suspicious of their boss's hostility towards them. Is he involved in the racket? And what is the truth behind the plane crash at sea in which Clint Hill,

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