This is the second book in the Illuminae files. It follows Hanna and Nik who are aboard the jump station Heimdall. Despite their differences, they are forced to work together to defeat BeiTech and their team of invaders. Meanwhile, the characters from the first book are racing to safety. I loved this book. Just as in Illuminae, it's told through emails, messages, military reports, and video analysis. I would recommend this to anyone who wants to read a sci-fy trilogy. Check it out!