It is 1941 and the Royal Navy are hard pressed to hold the enemy at bay. The Nazi army dominates Europe and in the North Atlantic U-boats strike at will. From the North Sea, down through the English Channel and into the Bay of Biscay, the battle for naval supremacy is hard fought.
For Lieutenant-Commander Richard Thorburn, Captain of the small Hunt class destroyer HMS Brackendale, the war has become an endless series of dangerous missions. Again summoned at short notice, Thorburn finds himself thrust into a battle where duty, compassion and raw courage will be tested to the full.