Bela Lugosi in The Wolf Man?
Upon hearing that this film was in the planning stages at Universal (and that Curt Siodmak was writing a screenplay), he lobbied extensively at the studio to play the part of werewolf Larry Talbot. In the final film, he was relegated to the small role of a gypsy (creatively titled "Bela" by Curt, more than aware of Lugosi's attempts at winning the lead).