While dodging accusations of communism, Charlotte Serber made the nuclear bomb possible.
Source: The Librarian Who Guarded the Manhattan Project’s Secrets – Atlas Obscura
Charlotte Serber, a University of Pennsylvania graduate, statistician, and freelance journalist who at one point interviewed Frank Lloyd Wright for The Boston Globe.
In 1942, J. Robert Oppenheimer selected Serber to spearhead the project in part because of her lack of librarian experience. He wanted someone who would be willing to bend the rules of cataloguing.
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As the head of the scientific library, she became the Manhattan Project’s de facto keeper of secrets, a position that soon saw her targeted for an FBI probe—and almost ended in her being fired from the project.
Serber’s greatest challenge proved to be importing thousands of esoteric textbooks, journals, and manuals to a town that isn’t supposed to exist—without raising suspicion.