Sarah Anders and Dan Kenyon sell their beautiful city apartment and buy an old mill in rural England. Their dream of an idyllic life is shattered when a woman arrives at their new home with a five-year-old boy she says is Dan's son whom they realise is on the autistic spectrum. Sarah knows nothing about Tobias. He is a secret Dan has kept from her. From that life defining moment, everything irrevocably changes.
When Sarah hears Tobias speaking fluently to someone when he's alone she recognises a name, one that devastates her and catapults her back twenty years. Memories she'd buried from a troubled childhood swiftly return to overwhelm her. When doubts creep in over what happened in the past and strange, frightening happenings at the mill shake her to her core, she begins to ask questions in the village about the murder of a child at the mill, and it's not welcome.
Unknown to Sarah, she isn't the only one who fears the return of her memories, and suddenly she and five-year-old Tobias are in fear for their lives.
'It's the other boy in the basement, ' said Tobias. 'The other boy telled me.'