When Sergeant Hallie Michaels returns home to South Dakota from Afghanistan on ten days' compassionate leave, her sister Dell's ghost is waiting at the airport to greet her. The sheriff says that Dell's death was a suicide, but Hallie doesn't believe it .... As Hallie pushes for answers, she attracts more ghosts--local women who disappeared without a trace--and discovers a disturbing pattern. Now she needs to not just figure out what happened to Dell but to make sure no one else shares her fate.