A vivid and comprehensive retelling of the pivotal rescue of the British Expeditionary Force (BEF) during the very early stages of WW II. Gelb (The Berlin Wall, Less Than Glory) provides more than adequate background on why and how war came to Europe for the second time in just over 20 years. He also documents the blitzkrieg Nazi Germany unleashed against its Western neighbors on May 10, 1940. In less than three weeks, the author recounts, the Wehrmacht had brought France to its knees and trapped the BEF against the sea around Dunkirk. As Gelb makes clear, the ensuing evacuation (beginning May 26) that saved almost 225,000 British and roughly 140,000 French troops to fight another day was more a deliverance than a triumph. In addition to a day-by-day log of key events on the congested beaches and in a perilous English Channel during the ten-day exodus, the author furnishes intriguing perspectives on reactions in global capitals. Washington, to illustrate, drafted plans to send US troops to South America to prevent a German invasion. While London's invasion fears were appreciably more credible, Churchill's new coalition government was still able to mobilize a ragtag flotilla and sufficient air cover to extricate the besieged BEF, albeit without much of its equipment. Gelb does not glamorize the role played by civilian vessels in the recovery. (The official records remain sealed, but many skippers and crews quit after making an under-fire trip.) Nor does the author discount the importance of good fortune: the channel was atypically calm throughout the rescue mission (codenamed Operation Dynamo), and Hitler contributed some vital tactical blunders. A balanced account of a fabled exploit, which sets a high standard for other reconstructions sure to follow as Dunkirk's 50th anniversary approaches. The absorbing text includes photographs and maps (not seen).