Zed is an operative who has been sent back in time. His mission is quite simple: certain events need to occur in order that society will eventually become perfect. Unfortunately, and rather depressingly for Zed, he is in charge of protecting the unpleasant events, such as assassinations, bombings and leaks of classified information, that need to happen in order for the perfect society to eventually happen. Even more importantly, he cannot become attached to the targets he is watching, and must try not to identify with them and their desire to create a better world now, rather than in the nebulous future that they will never see.
The plot is relatively simple, but the characterisation, which is so rich, enhances the story and makes it an excellent read. The almost parallel stories of Zed and Leo make the reader constantly wonder just what will happen next, and the payoff is absolutely unexpected – heart-rending and heart-warming at the same time. The characters grow and evolve as the story continues, until you feel a real connection with these people who have lives that you might not be able to imagine and yet eventually have come to empathise with. The pace of the story, which could easily have become too slow under the twists and turns of the plot, is maintained beautifully and keeps the reader interested throughout, without skimping on exposition. What seems like a sci-fi book quickly becomes a story about people, politics and the ridiculousness of the way the world is run, entertaining the reader and making them think at the same time.