Una Richardson is devastated after the death of her mother. Hoping for a fresh start, she responds to an advertisement and steps into the rich, comforting world of elderly Mrs Elspeth McKenzie.

But Elspeth's home is not as safe as it seems.

Kathryn, her cold and bitter daughter, resents Una's presence. More disturbing is the evidence suggesting two girls lived here before.

What happened to the girls?

Why will the McKenzies not talk about them?

As the walls close in around her, Una fears she'll end up just like the other girls . . .