According to legend Bela Lugosi turned down the role of the monster in Frankenstein (1931), this is not entirely true.
Robert Florey who had originally been assigned as director for the film, wanted Lugosi to play the role of Dr. Frankenstein but, Carl Laemmie Jr., the producer, did not want Lugosi for that role and recast him in the part of the creature. After several screen-tests with Lugosi as the creature, Laemmle was displeased with the results and fired both Florey and Lugosi. Laemmle then hired up and coming director James Whale who in turn cast Boris Karloff in the role of the creature.
Murders in the Rue Morgue (1932) was later produced as a compensatory package for Lugosi and Florey. This film performed poorly at the box office and as a result Lugosi's contract with Universal was not extended.