A leading naval and military historian presents the first book to cover the major submarine campaigns in all the WWII theaters. Vividly recreates the experience of submarine and anti-submarine warfare from the decision makers in the war offices to the men in the boats. Describes the disappointing performance of the giant Japanese submarines in the Pacific and the narrow margin by which Britain escaped defeat by German U-boats in the Battle of the Atlantic. Reveals new information about the capture of the Enigma cipher machine, harrowing accounts of defenseless warriors shot in the water and much more. Contains 16 pages of photographs, many published for the first time.