Sometime after the world has starved itself of oxygen and humanity has retreated to sealed domes, our three main characters find themselves bound together in an adventure. Alina, resistance fighter, who knows the pods are an excuse for the elite to hold on to power; Quinn, the son of one of those elite; and Bea, the daughter of one of the working classes, lovelorn for Quinn who never notices her (at first, anyway).It's a wonderful premise of a book, the world suffocating without oxygen, and the world building and descriptions of the wastelands outside the pod are great. It's the characters that let the book down a little. We shift from one perspective to another every chapter, first person every time, and perhaps that's the problem. I would have liked to have stayed in Quinn's head for longer to get to know him better, for instance. The characters voices are quite similar as well, such that I had to check the chapter headings to see who was speaking and thinking a few times.I would have enjoyed the book more if it had been about the end of the world, the time called "The Switch". Watching humanity fall apart into ruin was what pulled me into the book and the little flashbacks are what kept me interested. It would have been grim reading, I'm sure, but there are glimpses of the lost world that I felt needed exploring more. A character talks of when she was a death nurse, killing people who asked rather than let themselves slowly suffocate. Tell me what that was like rather than focus on the long-after. Write a prequel, maybe.Unusually, the love triangle is between two girls and one boy, rather than the other way round. I liked that. I liked there was a character who was gay and it was the least interesting thing about him. It's mentioned once and not again. He isn't defined by it as though it were his only attribute.There are inevitable loose ends - this is book one of at least two - and it felt like there was a slow build that will continue into the next book, and I never felt cheated out of the unanswered questions.Will I read book two in autumn 2013? I think I will, just to see where it all goes and how it all ends.