"Joe May", born "Joseph Otto Mandel", was a film director and film producer born in Austria and one of the pioneers of Cinema of Germany/German cinema.
After studying in Berlin and a variety of odd jobs, he began his career as a stage director of operettas in Hamburg before starting to make films from 1912 in Berlin. In 1902 he had married the actress Mia May (born Hermine Pfleger) and took his stage name from hers.
In 1915 he founded his own film production company, and began to produce a successful series of crime films, whose detective hero went by the name of Joe Deebs. Some of these were directed by May himself, others by Harry Piel. (Around the same time May also worked on the Stuart Webbs series of detective films for another company). In 1917 he gave Fritz Lang one of his earliest breaks in the film industry as screenwriter on the film Die Hochzeit im Excentricclub (Wedding in the Eccentric Club) and Lang also worked on other May films at this time.More Joe May on Wikipedia.