I am known as an author of nautical fiction set in the Royal Navy of Nelson’s time, but after the publication of the eighth book in my Alexander Clay series, I felt the need to try something fresh. My main love is the sea, so my writing needed to contain this element, and I have long felt drawn to the Battle of the Atlantic in World War 2.

This was the longest and hardest campaign of the war. German U-boats were on station there from the day Poland was invaded until the day Germany surrendered, locked in battle with allied escort ships trying to shepherd their vital convoys of merchantmen through to safety, often in appalling weather. It was also the only theatre where the whole war could be won or lost, and both sides knew it. About 3,500 allied ships were sunk, or almost two for each day of the war and over thirty thousand merchant sailors were killed. The German navy lost 783 U-boats and twenty-seven thousand crew, which was threequarters of the men who served. This rate of fatalities was the greatest of any service in any armed force in the Second World War. Yet it is a campaign that has been largely ignored by historical fiction, with the honourable exception of Nicholas Monserrat’s The Cruel Sea and C.S. Forrester’s The Good Shepherd (both published over sixty years ago). A fresh novel was long overdue, I concluded.

Sea of Wolves follows the lives of three main individuals caught up in the centre of the battle. Vera Baldwin, a codebreaker at Bletchley Park working on the German Naval Enigma codes, Otto Stuckmann a young U-boat commander and Leonard Cole, the newly appointed first lieutenant of the escort ship HMS Protea. Over a six-month period in 1941 we see the tide of battle ebb and flow across the ocean, as the three stories come together.