My name is Kate. I volunteer at a Missing Persons helpline - young people who have run away from home call me and I pass on messages to their loved ones, no questions asked. I don't get many phone calls, and those I do are usually short and vague, or pranks. But this evening a girl named Sophie called. I'm supposed to contact her parents to let them know their child is safe. The problem is, Sophie isn't safe. And Sophie is my daughter. If you like Clare Mackintosh, Katie Marsh, Kerry Fisher, Jenny Blackhurst, Rachel Abbott or Lisa Jewell then you will be utterly gripped by this psychological thriller with a massive twist you won't see coming.