In the 1940s, Hedy Lamarr built a career in Hollywood after immigrating from Europe. Her lasting contribution to her adopted country, though, is a technological innovation that each of us still uses on a daily basis. Alexandra Dean joins us to tell Lamarr’s remarkable story, which she documents in her new film “Bombshell: The Hedy Lamarr Story.” It screens Friday as part of Dallas VideoFest’s DocuFest.