The supernatural spectre known as the Gytrash is mentioned in Charlotte Brontë’s novel Jane Eyre just before Jane meets Mr Rochester. The gytrash is a localised Northern dialect name for a creature that can change its shape, but usually appears as a shaggy dog with large glowing eyes that terrorises benighted travellers. It is easy to see why these spectres are so pervasive and so popular as they encapsulate our nameless fears of dark lonely places and the ability of our imagination to populate these desolates spaces with nightmare creatures. The most general form of this creature is an apparition known as ‘the black dog’. It became a favourite of Victorian writers such as the Brontes and Conan Doyle, and it has transferred into modern horror fiction and film simply by substituting the unlit open road for the urban world of alleyways and children’s nightmares.