It's said that if the ravens ever leave the Tower of London, then the Tower will crumble and the kingdom will fall. Resurrected sorcerer Matthew Swift is about to discover that this isn't so far from the truth... One by one, the protective magical wards that guard the city are falling. This is not good news. This array of supernatural defenses - a mix of international tourist attractions and forgotten urban legends - formed a formidable shield that protects the city of London from threats that are known to no one. But what could be so dangerous as to threaten an entire city? Matthew Swift is about to find out. And if he's lucky, he might just live long enough to do something about it...