Devoured this book in a five hour session but can't quite give it five stars. It's a fast, easy read with a highly interesting and engaging first half and a disappointing ending. Point of view skips around three different characters but despite that they still seemed sort of underdeveloped. The plot moves along at a steady clip but nothing revealed is "shocking" - you constantly as though you are feel several revelations ahead of the characters.
For me, everything sort of unraveled interest-wise around the big reveal. Before that the tension and action and fear was really working for me and afterward it just seemed like a run-of-the-mill survival novel.