Irene is a professional spy for the mysterious Library, whose staff are sent to different realities to harvest dangerous and mystical fiction.
Irene has been posted to an alternative steampunk London along with her enigmatic new assistant, Kai. Their mission: to retrieve a dangerous edition of Grimms' Fairy Tales. But it has already been stolen.
In London's underground, the laws of nature have been bent – supernatural creatures and unpredictable magic stalk the land. The city is home to vampires, werewolves – factions that are all prepared to fight to the death for this book.
Irene must face a web of deadly danger, deception and secret societies. Her new assistant is hiding secrets of his own. Yet failure is not an option – the nature of reality itself is at stake . . .