4.5, easily. 
 A more in-depth review can be found here on my book blog! 
 This is my favorite book I've read this year. I don't know why it took me so long to read it but I am so so glad that I did. Literally the only thing I knew about the book was that there was something vaguely apocalyptic about the plot, that's it. Every page lead to more surprises and intrigue. If only it were longer!