U-505 was the first enemy warship the US Navy captured at sea since 1812. This is a new account of how Captain Gallery planned and executed the raid on his own initiative, and how his success almost endangered the war against the U-boats. On June 4, 1944 a US Navy antisubmarine task group in the Atlantic captured an enemy U-boat on the high seas. It was not the first time the Allies had taken a German U-boat as a prize, but the capture of U-505 was different. Captain Gallery and his Task Group 22.3 devised a risky plan to capture scuttled U-boats. This book analyses in detail Gallery's dangerous strategy, using contemporary sources to explore why he thought the reward was worth the instead of attempting to sink the next U-boat that surfaced among them, a destroyer escort would send off its whaleboat. Everyone else was to smother the U-boat with light gunfire to encourage its crew to abandon quickly. Unaware that the Allies had already cracked the German's codes and the capture of a U-boat could endanger that secret, Gallery hoped to capture the vessel's codes and coding equipment to read U-boat message traffic. The plan culminated in the capture of U-505 in early June, which nearly caused the exposure of the Bletchley Park codebreaking secret. Featuring contemporary photographs, specially commissioned artwork and 3D maps, this book is a fascinating exploration of one of the most controversial and dangerous raids, which could have changed the outcome of World War II as we know it.