Unicorns are unique not just for their startling singular horn but because people carried on believing in them long after dragons, griffins, manticores and a host of other fanciful creatures had been consigned to myth and heraldry. Suckling covers the ancient tales and rumours that began the superstition, the wide-ranging influence of this creature, the early confusion between the mythical unicorn and the rhinoceros, its adoption as a Christian symbol; its use in heraldry, and the value of its horn as powerful medicine.