Unable to return to the mainland, and with no means to communicate, the girls have to figure out how to survive. Being suburban girls, they have little to no outdoors experience and working out food, water, and shelter becomes a matter of trial and error -- a terrifying thought when there is a killer is there with them. And that's before they find that there is a much worse adversary out there!
Needing a distraction from politics, I could have embraced an intellectual classic, but I grabbed for a trashy survival/horror novel instead. It wasn't nearly as bad as I expected it to be. Yes, there were plot holes and some really stretched logic in the storyline, but the tension was kept at a high level and the story was full of irresistable cliffhangers. For anyone who likes clever characters, it was engrossing to watch the girls MacGyver their way out of their problems. But maybe more to the point, each of the girls were interesting and sympathetic. They had very distinct personalities, strengths, and weaknesses. It helped that they didn't snipe at each other but instead worked together to get through it.
The story itself has a wonderful dramatic arc that allows each of the girls to have a moment to grow and be tested. That I cared about their ability to face those fears was startling to me for a book that I had assumed would be a mindless scream fest.