.27 is a number Ruby hates.It's a number that marks the percentage of the population that has survived. It's a number that means she's one of the "lucky" few still standing. And it's a number that says her father is probably dead. Against all odds, Ruby has survived the catastrophic onset of the killer rain. Two weeks after the radio started broadcasting the warning, " It's in the rain. It's fatal and there's no cure," the drinkable water is running out. Ruby's left with two options: persevere on her own, or embark on a treacherous journey across the country to find her father-if he's even still alive.