Tom Swift and his pal Bud Barclay embark on one of the greatest scientific adventures of the century -- a daring underwater crossing of the Atlantic Ocean, equipped only with Tom's electronic hydrolung suits! Hundreds of miles from land, the hydrolung batteries inexplicably go dead and the two boys are dramatically rescued in the dark of night. Examination of their equipment reveals sabotage.

A complex clue leads Tom to believe there is a connection between the sabotaging of the hydrolung and the sinking of the SS Centurion--which went down in mid-Atlantic with a fortune in gold bullion and a world-famous statue aboard. After making good on their second attempt to accomplish the nonstop swim under the Atlantic, Tom and Bud are given the assignment of salvaging the Centurion's valuable cargo. To locate the sunken ship, Tom designs the aquatomic tracker, an astounding device that detects and identifies metallic and chemical traces left by an object in water, then tracks the object.

How the young scientist-inventor outwits the vicious saboteurs and traps the most fiendishly clever mastermind of crime he has ever met makes a fast-moving story of super-suspense.