When Mallory Dawson gets a call from a former colleague, Elsa, describing a strange scene, she initially thinks nothing of it. The teenage cleaner had gone into clean a holiday cottage in the forest to find a kettle boiling on the Aga, sandwiches half made and the family who were renting it gone.

DI Harri Evans, however, has a story about the place from the time he was in uniform. He was called out to a girl with scratches down her face claiming someone unseen had attacked her. When the father of the missing family is found dead in their hire car there is an urgent hunt for the rest of the family.

But their identities are false and there's no hint of their history. How are the past and present connected?