Valuable antique weathervanes are being stolen in the Pennsylvania Dutch country. A Navy employee removes a top secret document from the Pentagon. The Hardy brothers try to solve these two seemingly unrelated mysteries.
When a ferocious, wolf-life creature appears in a small town, the Hardy boys are engaged to clear the name of a young man who has a history of werewolves in his family.
A Japanese business tycoon mysteriously disappears and, soon after, a rare samurai sword is stolen from an art gallery. Suspecting a connection, the Hardy boys try to solve the mystery.