Ask people to name the most famous historical woman of science and their answer will likely be: Madame Marie Curie. Push further and ask what she did, and they might say it was something related to radioactivity. (She actually discovered the radioisotopes radium and polonium.) Some might also know that she was the first woman to win a Nobel Prize. (She actually won two.) But few will know she was also a major hero of World War I. In fact, a visitor to her Paris laboratory in October of 1917 – 100 years ago this month – would not have found either her or her radium on the premises. Her radium was in hiding and she was at war.