Okay, this was somehow weird. 
 The beginning was exciting, mysterious and well-established. The ending was just the same. But the 200 pages inbetween were ... yes, weird. Our protagonist, Ethan, did nothing but run, hide, run, hide, run, hide and - you wouldn't think so - run. There wasn't anything particularly exciting about it, since you always knew he would be going to survive this torture, and the author every time seemed to want to remind the reader of how good his running scenes were. Except they weren't. 
 As the ending was very well-written, though, and made up for another nice story, I have ordered the second and third volume to read them as well. As to the ending (which I will not be spoiling now), the second book is supposed to be less suspenseful and not full of action, but more about character development, which I'm very glad of. 
 Blake Crouch's writing style was exhausting. 
 Literally. 
 Exhausting. 
 And so were those sentences. 
 Paratactic. 
 And exhausting. 
 So, so exhausting. 
 The characters were relatable, especially Ethan and Theresa, but I still have the feeling to not really understand them. 
 I'll rate this with a good three-stars-rating. And, perhaps, the second and third volumes will be able to surprise me.