Biomedical engineer Lance (Duke Univ. Sch. of Medicine; In the Waves) offers her distinctive perspective on the previously classified story of how underwater engineers during World War II willingly exposed themselves to extraordinary life-threatening risks to make D-Day successful. She vividly describes how brave, eccentric researchers experimented on themselves to understand better the science of lethal undersea pressure and underwater breathing apparatuses to provide support for the Allied invasion. These courageous researchers undertook life-threatening risks as they investigated new technologies and scrutinized Normandy beaches, underwater sea floor mines, and defensive construction. Lance immersed herself in declassified intelligence and includes striking descriptions of the personalities of the maverick scientists who risked their lives in their endeavor. British actor Alex Wyndham’s distinctive baritone is an impressive match to this account of little-known details from the perilous preparation for the Normandy invasion. VERDICT Lance’s important work reveals how chamber divers helped develop much of the technology that has enabled today’s popular underwater diving and military stealth diving. Her work significantly updates and expands R. Frank Busby’s Manned Submersibles and Robert F. Marx’s The History of Underwater Exploration. This one is destined for Hollywood and is essential for all World War II collections.