The story of the most desperate conflict of the Second World War - The Battle of the North Atlantic, as it was fought by one of the Royal Navy's Flower-Class Corvettes and later by one of the latest Frigates. Like every good novel, it's essence is true. 
 The protagonists learn to deal with the enemy's implacable and merciless U-boats and reconaissance aircraft, and to endure the bitterness of the steady losses from one convoy battle to the next. Meanwhile, even in the enemy's absence, their primary struggle is against the cruel sea itself, an equally implacable and merciless foe.