It's 1941, and the fate of the world hangs in the balance. Across the stormy North Atlantic rages a battle between wolfpacks of U-boats and escort ships fighting to protect the Allies’ vital convoys. Meanwhile, teams of codebreakers at Bletchley Park struggle to penetrate the German Navy’s Top-Secret Dolphin code to unlock the flow of vital intelligence that will swing the battle in the Allies' favor.

After a century of war, revolutions, and imperial conquests, 1790s Europe is still embroiled in a battle for control of the sea and colonies. Tall ships navigate familiar and foreign waters, and ambitious young men without rank or status seek their futures in naval commands. First Lieutenant Alexander Clay of the frigate Agrius is self-made, clever, and ready for the new age. But the old world, dominated by patronage, retains a tight hold on advancement.

December 7, 1941 - America is attacked by the Japanese and dragged into a worldwide struggle for power unlike anything ever seen on Earth. While the United States and the Navy reel from the devastation of Pearl Harbor, the Nazis begin a brutal campaign within sight of the shores of the nation. U-boats prowl the American coast from Maine to the Gulf of Mexico, sinking shipping seemingly unopposed!

In August 1939, Duncan Morant, the only son and heir of the second Lord Eversham, is enjoying life as a man-about-town, skippering his racing schooner Kristin. But Duncan is also a sub-lieutenant in the Royal Naval Volunteer Reserve, and as the war clouds gather, he is called up.

When Jox McNabb is expelled from school he is forced to look to his future. Inspired by the sight of a Hurricane flying over him, he becomes determined to join the RAF. And after basic training, Jox is posted to RAF Montrose with the growing group of other recruits he has met along the way.