Former lawyer Merrin McKenzie has returned to her hometown of St Ives, the stunning coastal town in Cornwall. She has settled back into life there in a lovely cottage, and new friendships are beginning to blossom. An old friend, Jane Faulkner is going through a messy divorce, and her daughter Emily is keen to stay with Merrin, but just three days into the holiday, she disappears. Emily has pushed a note through Merrin's bedroom door to say she is going back home to Bristol but has left behind all of her possessions. It soon becomes clear she is not heading home and the police are notified, but when a ransom demand is made to her parents requesting £500,000 for the girl's safe return, matters take a distinctly sinister turn .