Recruited by the U.S. Army and Navy from small towns and elite colleges, more than 10,000 women served as code breakers during World War II. While their brothers and boyfriends took up arms, these women moved to Washington and learned the meticulous work of code-breaking. Their efforts shortened the war, saved countless lives, and gave them access to careers previously denied to them. A strict vow of secrecy nearly erased their efforts from history. Now, through dazzling research and interviews with surviving code girls, Liza Mundy brings to life this riveting and vital story of American courage, service and scientific accomplishment.