She made eight films for MGM between 1938 and 1945: Lady of the Tropics (1939), I Take This Woman (1940), Boom Town (1940), Comrade X (1940), Come Live with Me (1941), Ziegfeld Girl (1941), H.M. Pulham, Esq. (1941), Tortilla Flat (1942), Crossroads (1942), White Cargo (1942), The Heavenly Body (1944), and Experiment Perilous (1944). Not all of these were successes. Several were widely acknowledged, at the time, as the kind of material that failed to use her well — vehicles that gave her a look but not a character, a glamour but not a scene.
The studio system of the 1940s was not designed to take women’s intelligence seriously. An actress was a face, a voice, a body moving through scenes written by men, directed by men, produced by men, and photographed by men. If she was extraordinarily beautiful, as Lamarr was, that beauty was the primary thing the studio thought about when deciding which pictures to put her in. Directors who worked with her — and she worked with some of the best, including King Vidor, who directed H.M. Pulham, Esq. — noted that she was intelligent, professional, and technically precise. She knew where the camera was. She thought about light and angle. She prepared. But the system was not built for that kind of preparation to show.
Between studio assignments, she used her time differently. She had a workshop installed in her home. She experimented with small mechanical projects — an improved traffic signal, from one account; a carbonated beverage tablet, from another. These projects were real in the sense that she worked on them, and speculative in the sense that none of them reached the market. They are mentioned here not as proof of engineering credentials she did not formally hold, but as evidence of a habitual kind of curiosity. She took things apart to understand how they worked. She put them back together differently. This was not the behavior of someone who happened to be beautiful.