Who can you trust if you can`t trust yourself? Lizzie lives in the Lake District with her partner, Jonty, & his teenage son, Sam. Though she`s only ten years older than her stepson, their set-up works. They are a family. Then Sam becomes sullen & withdrawn, & Lizzie suspects something sinister is going on. But no one will believe her. They think Lizzie is to blame. Are they right?