I thought this book was very good because it had a very good characterisation of teenagers going through a turbulent time, and captured the emotions and stresses of teenage life very accurately. It portrayed everything vividly and believably, though I thought the character of Sim was a bit angrier than he would be in real life. I thought the chapter with the bungee jump was a particularly good visualization of character. There was excellent description all through the book, and the general atmosphere was nicely tense and fraught. However, I thought the plot was very unrealistic, though the motivation of the characters to  carry  out the task and the way they did it was realistic. The ending was a very good chapter; Gray captures the desolation of the scene and it is a moving end to the book. This is a good book and I give it 8/10.