Kady and Ezra broke up, then their planet was invaded. The former couple escapes the planet but their problems aren't over yet. Three ships filled with refugees are trying to get across the universe to the next bit of civilization while being chased by their invaders. Disease, resource limitations, and a potientially crazy AI are all threatening their ability to survive. 
 This book is an epistolary novel, so if that isn't your jam I'd pass on this book but if you like Sci-fi and epistolary novels pick this book up because it's really solid. It also immediately made it on my list of book to buy a physical copy of. Have you seen the dust jacket and cover? It's amazing and a quick flip though the book shows you how beautiful the art in this book is. There are some clunky bits of this story but they didn't impact my enjoyment of the story or the way that it was told. I can't wait for the next book(which is apparently both a sequel and also a companion novel) and I'd obviously recommend this book. 
 Okay now on to some if you've read the book stuff. 
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 The phobos virus and AIDEN. Phobos is terrify, AIDEN is also terrifying and I can understand why AIDEN nuked the ship but holy crap. Also I looked up Kady's mom right away so I didn't get the like reveal feels when she finally told Ezra but it was still really sad to see all the requests and emails and realizing her mom was probably dead before the ship exploded. Also loved the easter egg(is that what you would call it) of the patients name in that section of the book. 
 When Kady goes over to the Alexander and then we find out Ezra isn't even there, and then that he's dead. I never thought he was dead I kept going no, that can't be true, and then it wasn't and I was so happy. I did find it strange when I was reading that Ezra went from hearts and the rose to the full detailed face, and I'm surprised I didn't pick up right away that it was AIDEN doing it. Looking back on it it should have been obvious but that whole section was so intense I wasn't looking for the larger things going on but rather the next line of text. 
 Byron. I loved him as a character especially when we started seeing him through more than just messages. I loved the logic bomb idea and how that came together. I love that you saw him fighting AIDEN and the virus at the same time.His death was so amazing and hit me the hardest. 
 Also I started feeling for AIDEN even though the idea of him...it...creeps me out big time. 
 I did find the whole Ezra's mom reveal to be a little clunky. I liked what they did at the end but up until then it mostly just bugged me. 
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