Across the stormy North Atlantic, battle rages 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, and unlock the flow of vital intelligence that will swing the battle in the Allies' favour.

Sea of Wolves plots the lives of three people caught up in the centre of the battle. Vera Baldwin, a young crossword-enthusiast, lifted from her quiet suburban life and thrown into the middle of the greatest codebreaking effort the world has seen. Otto Stuckmann, the rookie commander of U70, a German naval veteran struggling with the ceaseless demands being placed on him. Leonard Cole, the newly appointed first lieutenant of HMS Protea and a man with unfinished business to resolve.

Each is unknown to the others as their fates spiral around each other, touching and twisting towards a final encounter that will change their lives forever.