I started off loving this newest YA fantasy/science fiction offering from Ally Condie, who wrote the very popular "Matched" series. Cool concept: humans poisoned the world, and had to Divide the population between those who'd live short, sick lives Above and the loved ones they sent to live safely Below. The Below depends on the Above for food and maintenance, and the two societies share a religion that encourages continued assistance from the Above. Rio, our protagonist, has just lost her mother (to a suspicious death) and sister (who chose to go Above, even though they had both decided to stay Below). The double loss is almost more than Rio can take, and the added pressure of concealing her true nature as a siren - one whose voice has the power to sway people's thoughts and emotions - eats away at her self-control. She immediately begins hatching a plan to escape to the Above and find her sister.
Like I said, it's a cool concept, but the writing leaves something to be desired. Important plot-jumps are made very suddenly and with little sense. Rio and True fall in love, but only because YA novels dictate there has to be a love interest; there's nothing in their interactions that indicate they even care for each other as more than colleagues, let alone love each other. And the reveal of the villain's secret was similarly sudden, described as pieces falling into place that were completely unforeseeable to the reader. Crazy plot twists are no good if they're totally out of the blue. Readers like to feel smart, like they might be able to guess what's coming, even if they can't. These things happen without warning, and so there's little tension generated in the story. It's choppy and threadless, and I'm disappointed that such a great idea falls so flat.