In 1940, while acting alongside Jimmy Stewart and Judy Garland in the MGM musical Ziegfeld Girl, the 26-year-old Lamarr spent her free time devising a radio-controlled submarine missile-guidance system to help the U.S. Navy in World War II. What moved her to do this? “She didn’t drink and she didn’t like to party, so she took up inventing,” Rhodes explains.

Hedy Lamarr Biography: Hedy’s Folly by Richard Rhodes (Review) - The Daily Beast