This is the story of the British submarine service in the first World War, something which barely gets mentioned in general histories of that war. The reason for this, according the Edwyn Gray, is the misuse of the service by the Admiralty. In the North Sea, at least, the submarines were used primarily for fleet service and shore defense, unlike their German counterparts, who were unleashed to create havoc on virtually anything afloat. There were exceptions during the war in which the British submarines were allowed a more predatory role: in the Baltic and in the Sea of Marmora during the Gallipoli campaign. Those brief, harrowing episodes form the most interesting part of this book. Gray was writing for a British audience 50 years after the war, but he did a good job of telling the story in a breezy, journalistic style. His tendency on occasion to glorify war or depict it as some kind of game is a little off-putting to the modern reader, but I did learn a lot about the role played by what must have been some of the most courageous sailors ever to put to sea. ( )