Answer: in a new documentary called Bombshell: The Hedy Lamarr Story
Hedy Lamarr, an actress known for her roles in the 1938 film Algiers and the 1949 film Samson and Delilah, was also one heck of an inventor.
In 2014, she was inducted into the National Inventors Hall of Fame for her work at the beginning of World War II with composer George Antheil in developing a radio guidance system for Allied torpedoes. This system used spread spectrum and frequency-hopping tech to defeat the threat of jamming by Rome, Berlin and Tokyo.
Although the U.S. Navy didn't adopt the tech until the 1960s, the principles of Lamarr and Antheil's work are now incorporated into modern Wi-Fi, CDMA and Bluetooth technology. This is because when the duo's patent lapsed, the schematics for their system became public domain — and other engineers could then study and interpret the design.
It was this wartime invention that earned Lamarr the "Mother of Wi-Fi" title. And a new documentary, called Bombshell: The Hedy Lamarr Story, shows "how Lamarr's beauty and scandals kept many from appreciating her more intellectual achievements," Engadget's Cherlynn Low wrote. "And sadly, in its effort to cover every aspect of Lamarr's eventful life, the documentary doesn't spend quite enough time putting into perspective the impact of her invention."