Originally designed in 1934 for anti-submarine training, by the end of the war 72 U-Class subs had been commissioned; 17 were lost to the enemy, and 3 in accidents. Manned by crews from seven nations' navies, they served worldwide, and never more successfully than in the Mediterranean. This book is the definitive study of this class of submarine and the men who serve on them.

Derek Walters is an author and historian.