I received this on a read to review basis from NetGalley. Thank you to the author, Blake Crouch, and the publisher, Crown, for this opportunity. 
 For the first few chapters of this book I was lured into the false sense of this being another stereotypical thriller. It was honestly what I wanted at the time: something that provided some cheap thrills and yet was not too far out of my comfort zones. This novel set itself up to be just that. We meet Jason Dessen and his perfect, happy-families life, of which he is seized from by a masked abductor. So far, so read before. What follows was totally unprecedented and this continued to blow my mind from start to finish. To tell you who the abductor was or what was wanted from their victim would be to spoil the fun of this novel - this is something best dived into with no preconceived conceptions. 
 The cleverness of this novel is astounding and I can only imagine the research and work that must have gone into making this appear so technologically and scientifically sound - at least to the layman. Not only does this provide amazing repeated world-building, but the believability of this scifi-meets-thriller tale made this an astounding and chilling read. I was drawn into this story and the characters, and the ending was a perfect summary to conclude this epic read.