First things thirst, this novel doesn't fit into one genre. It isn't just a sci-fi, an action, a survival. It's all of them - and many more.
Second, this also claims to be "an unsentimental love story, a tale of human resilience and a novel for our times". Of all these assurances, I say only the latter is true. The love story aspect is dulled by the strong storylines featured, and at many times I wondered whether the protagonists were too ordinary to be called "resilient" or had just given up on life - at many times, Charlie struggles with depression and is at breaking point.
However, one thing I can say about this novel is that it is incredibly gripping. I could not put it down and wanted to know what happened ASAP! As all Muchamore books are, this was addictive and featured many unpredictable plot twists. All in all, I would recommend this to a friend or foe: it's that good. His first standalone - this book - is extremely worth the wait and I'm looking forward to reading his next novel, Arctic Zoo, coming out in 2019.