Don Winslow of the Navy #5

When Commander Don Winslow patrols the waters between a trapped German battleship and the American U.S.S. Carolina, a tiny three-man Nazi submarine surfaces with a daring plan: to knock out the American crew with anesthetic gas and steal the battleship itself. Winslow and his companion Red must fight off the German saboteurs and stop a plot far more cunning than a direct attack—one that could hand the Nazis a powerful new warship and free their own vessel to raid the Atlantic.

When Don Winslow captures a spy sending supply ship coordinates to Japanese submarines, he thinks the case is closed—but a third vessel sinks that very night, revealing a far more dangerous operative still at work. With Admiral Colby's daughter Mercedes waiting for a date that keeps getting postponed, Don and Red must hunt an "Unknown Spy" whose signaling method remains invisible to every detection device at their command. As ships continue to vanish and clues stay maddeningly out of reach, Don's legendary instincts face their greatest test yet.

Commander Don Winslow races to solve a baffling mystery threatening an entire American convoy bound for Europe—a phantom Nazi submarine that strikes without warning and leaves no trace. When Private Hank Lawson spreads rumors of an "invisible sub" that sparks fear through the fleet, Don and Red go undercover as soldiers to track down the truth, only to discover that the real threat may be far closer than they thought. As the convoy plows through darkness, sabotage and treachery lurk beneath the waves.

Don Winslow and Red Pennington's reconnaissance flight takes a disastrous turn when their plane malfunctions and ditches in the Pacific near a supposedly cleared island in the Solomons. After swimming ashore and scouting the jungle, Don makes a shocking discovery: a hidden Japanese air base, fully stocked with bombers that could devastate the American convoy arriving in just two days. Trapped on an island crawling with enemy soldiers and facing a dangerous trek through the jungle, the two naval officers must find a way to reach the Allied army camp and warn of the threat before it's too late.