The Yorkshire city of Willingsley is full of straight-shooting, gobby northern folk going about their day to day lives, with their love affairs, their health problems and all of life's other nonsense grinding on day after day. And then, suddenly, monsters come to town and people start dying. At the center of it all is Eric Mayfair, a twenty-something who a year ago was facing imminent heart failure. Fatal. Terminal. That's what the doctors said. And then, miraculously, Eric got better. He doesn't know how. No one does. All he knows is he has a new heart, a great black leach of a thing embedded in his chest that no one else seems to see. Then someone close to Eric is murdered and, in his search for answers, Eric uncovers an unseen world of monsters, dark powers and deadly secrets.