For centuries, the people in the east of England have told stories about a ghost dog called Black Shuck. According to the legend, the animal can be the size of a calf or as big as a horse. It has long black fur and huge, red or green fiery eyes. In some versions of the legend, it has only one enormous eye in the middle of its head. Black Shuck appears mainly in East Anglia, especially on the coast. It also appears in graveyards, on deserted side roads, at crossroads or in dark forests.

Traditionally, seeing the ghost dog brings bad luck. For example, in parts of East Anglia people believe that the person who sees Black Shuck will die before the end of the year. But in other versions of the legend, the animal is a friendly creature that helps lost travellers or accompanies women walking home at night.

The earliest surviving description of Black Shuck comes from a twelfth-century manuscript. But some scholars think that the story is much older and may go back to a Scandinavian myth of the god Odin and his black wolves, brought to East Anglia by the Vikings when they settled there in the ninth century.