After a heart attack, Niall Petersen is revived on the London Underground by an old lady who tells him he’s not entirely human. The old lady turns out to be much older than she appears, and explains that he has inherited the bloodlines of the Feyre, creatures of myth and folklore. Now one of those creatures is hunting him and he must find a way to survive. To succeed he must discover the secret of the two knives, one blunt, one sharp, the six horse-shoes, and why there are Sixty-One Nails.