CODENAME NEMO

An account of World War II codebreaking focused more on action than brainwork.

Lachman, executive producer of Inside Edition and author of The Last Lincolns and Footsteps in the Snow, explains that the typewriterlike enigma machine generated critical Nazi communication by scrambling input in billions of ways, and German experts never doubted that its code was unbreakable. However, by 1941, the British were deciphering many messages by ordinary codebreaking brilliance, aided by the earliest computers; despite these successes, actual possession of an enigma machine would make their work easier. All U-boats carried one, but crew invariably destroyed it when threatened with capture. No history of the enigma program—including perhaps the best, Stephen Budiansky’s Battle of Wits—neglects the story of how the Allies hit the jackpot on June 4, 1944, but Lachman tells the fascinating story from the beginning. Opening the book with the U-505 launch in August 1941, the author describes its German crew, the often grotesque conditions inside a U-boat, and the nearly three years of campaigning that featured far more tedium and terror than successful attacks. Lachman does the same with significant American ships and sailors, including Daniel V. Gallery, leader of the antisubmarine task force who, unlike other commanders, had publicly vowed to seize a machine. Few readers will object as Lachman recounts the background, and they will perk up just past the halfway point, when he chronicles how sonar detected U-505. In earlier years, the Allies had captured U-boats, though never fast enough to prevent destruction of its secrets, but Gallery had a trained team ready to go. The author delivers a rousing account of its success. Though Lachman doesn’t claim that the capture of U-505 shortened the war, it was a genuinely heroic act that the author recounts capably.

A satisfying World War II history.