Days later, the arrival of her passport and a note that reads "I'm sorry--S" sets off real alarm bells. He vows to do whatever it takes to find her. Adam is puzzled when he connects Sarah to a cruise ship called the Celebrate--and to a woman, Estelle, who disappeared from the same ship in eerily similar circumstances almost exactly a year before. To get answers, Adam must confront some difficult truths about his relationship with Sarah. He must do things of which he never thought himself capable. And he must try to outwit a predator who seems to have found the perfect hunting ground ...

    A single mother and her boyfriend both stabbed to death. A sordid history of violent crimes, repeated over and over--but decades apart. . .Unrelenting FearOlivia Barker is a therapist with no connection to the murders. But she has heard things. Stories that keep her up at night. Details that only a killer would know. A killer who could be one of her patients. . .Unspeakable TruthOlivia has no proof for her suspicions. But as the body count rises, so do her fears. A rock is thrown through her window; her car tires are slashed; a chilling message is scrawled on her bathroom mirror. Olivia knows she's getting closer to the truth. But the truth could be the last thing she'll ever know...

    She knows it will wait at the same signal each time, overlooking a row of back gardens. She's even started to feel like she knows the people who live in one of the houses. 'Jess and Jason', she calls them. Their life - as she sees it - is perfect. If only Rachel could be that happy. And then she sees something shocking. It's only a minute until the train moves on, but it's enough. Now everything's changed. Now Rachel has a chance to become a part of the lives she's only watched from afar. Now they'll see; she's much more than just the girl on the train...