David Harwood is hoping a carefree day at Five Mountains will help dispel his wife Jan's recent depression. Instead, a day of fun with their four-year-old son Ethan turns into a nightmare. When Jan disappears from the park, David's worst fears seem to have come true. But when he goes to the police to report her missing, terrified that she's planning to take her own life, the facts start to indicate something very different. The park's records show that only two tickets were purchased, David and Ethan's and CCTV shows no evidence that Jan ever entered the park at all.

Suddenly David's story starts to look suspicious - suspicious enough for the police to wonder if she's already dead, murdered by her husband. To prove his innocence and keep his son from being taken away from him, David is going to have to dig deep into the past and come face to face with a terrible childhood tragedy - but by doing that he could risk destroying everything precious to him.