1940. 20-year-old Charlotte Richmond watches from her attic window as enemy planes fly over London. Grieving her beloved brother killed in France she is working hard to keep going: working her dull typist job sharing confidences with her best friend Elena and dodging her father. She keeps her head down - she knows what happens when she makes a nuisance of herself. A source of joy is seeing the boy who feeds the birds on the way to work but every day brings new devastation. After another loss Charlotte has an uncanny sense of foreboding. Someone is stalking the darkness targeting her friends. Following her. She doesn't know who to trust. She can't trust herself - her family have told her so often enough. As grief and suspicion consume her Charlotte's nerves become increasingly frayed and soon her very freedom is under threat. . .