Russell Ball, MGM publicity photographer · Public domain

Nicknamed "The Boy Wonder," Thalberg was running MGM's production slate by age twenty-six, shaping the studio into Hollywood's most successful through an eye for scripts, casting and craft that produced Grand Hotel, Mutiny on the Bounty and The Good Earth. He had been told as a child, after a congenital heart condition diagnosis, that he wouldn't live past thirty; he built one of the most influential careers in studio-era cinema anyway before dying at 37.