In 1939, he made another serial for Universal called "Buck Rogers". Like "Flash", it was based on a popular science fiction comic strip. Crabbe was paid $1,000 per week. Universal made Crabbe's third and final Flash Gordon serial, "Flash Gordon Conquers the Universe" in 1940. Crabbe was paid a flat $25,000. He became known as "The King of the Serials". He had made five serials for Universal and owed Universal (not Paramount) the stardom he had won.