The Phantom Freighter

When a renowned scientist disappears along with his high-tech invention, Frank and Joe Hardy are determined to find him, leading them to a mysterious freighter adrift in the Atlantic. In another adventure, they join eccentric Thaddeus McClintock on a sea voyage, becoming entangled in a mystery involving blocked reservations, phantom freighters, and slippery smugglers. Throughout, they also assist their detective father in solving a case of counterfeit historical documents, combining action, mystery, and suspense in their pursuits.