The first drug overdose comes just after midnight, when a young woman dies on the dirty floor of a gas station bathroom. To the people of the small town of Acker's Gap, West Virginia, it is just another tragedy. It is sad--but these days, depressingly familiar. But then there is another overdose. And another. And another. Prosecutor Bell Elkins soon realizes that her Appalachian hometown is facing its starkest challenge yet: a day of constant heroin overdoses from a batch tainted with a lethal tranquilizer.