A woman with wings that exist in another dimension. A man trapped in his own body by a killer. A briefcase that is a door to hell. A conspiracy that reaches beyond our world. Breathtaking SF from a Clarke Award-winning author.Tricia Sullivan has written an extraordinary, genre defining novel that begins with the mystery of a woman who barely knows herself and ends with a discovery that transcends space and time. On the way we follow our heroine as she attempts to track down a killer in the body of another man, and the man who has been taken over, his will trapped inside the mind of the being that has taken him over. And at the centre of it all a briefcase that contains countless possible realities.Tricia Sullivan returns to the genre with a book that will define the conversation within the genre and will show what it is capable of for years to come. This is the best book yet from a writer of exceedingly rare talent who is much loved in the genre world.