This terrifying thriller unfolds as pregnant Rachel and her husband, Matt, are stranded after wrecking their car on a remote Scottish road. Though hostile at first, a nearby farmer and his wife welcome them in after learning that Rachel is with child. Suddenly, Rachel realises the family's "daughter" is a local girl who'd gone missing years before. But when she and Matt attempt to escape, they're held at gunpoint - just as Rachel goes into labor. Will their child's first day on earth be the couple's last?