Paul Cain (pen name)

George Caryl Sims (May 30, 1902 – June 23, 1966), better known by his pen names Paul Cain and Peter Ruric, was an American pulp fiction author and screenwriter. He is best known for his novel Fast One, which is considered to be a landmark of the pulp fiction genre and was called the "high point in the ultra hard-boiled manner" by Raymond Chandler. Lee Server, author of the Encyclopedia of Pulp Fiction Writers, called Fast One "a cold-hearted, machine-gun-paced masterwork" and his other writings "gemlike, stoic and merciless vignettes that seemed to come direct from the bootlegging front lines."

Sims enjoyed a brief career in Hollywood as a screenwriter during the 1930s and 1940s, including writing the screenplay for the Boris Karloff vehicle The Black Cat.