What if you could record your state of mind, and then play it back any time you wanted? Having a good day at work, when you’re ultra-focused and everything falls into place? Why not record that feeling and then recreate it every day? And what if you could play back not just your own mental state, but also those of other people? If you’re anxious, depressed, or stressed out, you could relax by feeding in the zen-like calm of a meditating monk. The benefits for mental health and wellbeing could be immense… couldn’t they?

Unfortunately, nothing is ever that simple where human nature is involved. When scientist Kel Rafferty stumbles across a technique for recording and playing back brain activity, she pictures only the potential benefits of her invention – but when her device gets into the hands of the public, there is no limit to the sinister and depraved uses that people find for it.

This story builds a rich near-future reality, ambitiously switching between the perspectives of a large number of characters to create a city and a world with great depth. Rather like in Tolstoy’s Anna Karenina, in most cases the main characters’ lives do not overlap that much, but most of them are affected by Kel’s creation in some way, and their stories all add to the reader’s understanding of the world into which the device is introduced. The rapid shifts of perspective with each chapter are handled well, and while some of the characters are – perhaps inevitably – more engaging than others, I found that each thread held my interest until the novel’s end.