The film contains two references to the most famous vampire novel, Bram Stoker's "Dracula". First, Dr Chagas lives in lodgings at 4 Renfield Place, Whitechapel. In the novel, Renfield is the insect-eating inmate of Dr Seward's lunatic asylum. Second, Brother Marstoke tells Holmes that Brother John was murdered in an alley opposite 128 Demeter Street. The Demeter is the name of the ship in which Dracula sails from Transylvania to England.