This book was absolutely wild. From start to finish it was insane and I still think about it daily. I actually think thrillers are a great genre for Colleen and I think she wrote this really well as I was guessing all the way until the end (and even after). 

All of the charterers were bat shit crazy. I did feel sorry for Lowen in some parts put she did extremely questionable things too. After reading the bonus chapter, I’m even more convinced that Jeremy is a serial killer. He’s murdered two people with no remorse and I don’t think Verity was the first and if Lowen doesn’t get away asap, she will be next. Even Cash was creepy as fuck. 
As for manuscript vs letter, I’m team manuscript. I truly believe Verity was the craziest of them all. I’m not even a mother and I could never write that about a child. If she did write it as ‘practice’ for a novel, surely she would include some sort of disclaimer. 
However, Jeremy was also extremely odd. I definitely believe that there was at least a small chance he knew what Verity had done to Harper, as when Lowen showed him the manuscript he hardly read more than a chapter before he decided to murder his wife.

Overall, everyone was absolutely mental in this story. This book was insane from start to finish and I will never not recommend it to absolutely everyone. The way Colleen wrote this book is amazing, it left me feeling like was the crazy one this whole time, I don't think i will ever stop thinking about this.