Margaretha Geertruida Zelle was a Dutch born, German spy during World War I in Europe. She adopted the name Mata Hari as an exotic dancer working in Paris she quickly assimilated into the underworld of espionage and became a seductive dancer. She contributed to German victory, but after the war she was rounded up by the Dutch and put to death by firing squad. Her head was embalmed after her execution, but it has never been located, which led to the rumor that the squad's guns had actually been filled with blanks and that she was in reality alive somewhere, possibly Argentina. However, mainstream historians and scientists dispute these claims.
Many books, and at least two movies, have been made about Mata Hari and her espionage.