‘You’ve already crossed the line. You are in. In. and there is no out for either of you.’ Sadie McLure wants to find her family’s killers. Noah Cotton needs to know what drove his brother insane. Their search for answers will throw them into the astonishing world of the nano — where biots and nanobots battle for supremacy, and the twitchers who control it all fight to stay sane. It’s a fight for free choice. Every day could be their last. They’ve never felt more alive.