Cry of the Werewolf (1944) starring Stephen Crane, Nina Foch

Celeste, a Romany princess visits a paranormal museum where the curator Dr. Morris is writing the history of her werewolf mother, Marie LaTour. Shortly after her visit to the museum Dr. Morris is murdered. The police automatically suspect Elsa, his personal assistant. So the deceased Dr. Morris’s son Robert aka Bob, with Elsa’s help investigate what really happened to Dr. Morris.