U. S. Navy Lieutenant Gregg Masterman, of The Harvard and Boston Back Bay Mastermans, learned about the sea while winning silver cups sailing his yacht. He climbs swiftly in rank, and is now Junior Aide to Rear Admiral Stephen Thomas.

Jim Fletcher, waking up from a coma, finds he is to be given a court martial for treason and charged with informing on fellow inmates in a Japanese prison camp during WWII. Escaping from the hospital he tries to clear himself by enlisting the aid of Martha Gregory, widow of a service buddy he was accused of informing on. Helped also by Ted Niles, a surviving fellow prisoner, he gets closer to finding the answers he needs, and becomes ensnared in a grandiose scheme involving his Japanese ex-prison guard, $10,000,000 of US currency forged by the Japanese and a burgeoning crime network poised to wreak havoc throughout southern California.