The Royal Navy’s Captain John Walker was the most successful anti-submarine commander of the Second World War.

Having specialised in the unfashionable art of submarine hunting, his skills came to the fore with the increase of U-boat peril in the Atlantic Ocean.

He provided much of the template for anti-submarine warfare during the war which together with his bravery and determination would result in him sinking more U-boats than any other commander during the War. This is the story of his remarkable exploits which have drawn comparisons with some of the greatest naval commanders of all time and he has frequently been described as Britain’s greatest fighting naval commander since Horatio Nelson.