Known as “America’s first female cryptanalyst,” Elizebeth Smith Friedman was a master codebreaker who played a pivotal role in both world wars, but for many years, no one knew what she had done—not even her own family.

Elizebeth didn’t set out to be a codebreaker. In 1917, she was a 23-year-old English lit major, looking for an interesting job. That all changed when an eccentric millionaire whisked her off to his lavish country estate and recruited her to work on his passion project: finding the secret codes in Shakespeare’s plays. Elizabeth scoured the texts alongside a tiny team of self-taught codebreakers. No hidden messages surfaced. But soon, the U.S. government came knocking with a slightly higher priority mission. Perhaps her greatest coup was when she uncovered a Nazi spy ring in North America during World War II. J. Edgar Hoover took credit on behalf of the FBI, while Friedman signed an NDA, never speaking of her achievements, and fell into obscurity. Records of what she had done were found in the National Archives annex in College Park, Maryland.