London, 1944/45. Kate Henderson is an energetic and spirited young woman. As a trained paramedic and ambulance driver she does her work courageously and with determination, even though underneath she is still wrestling with grief after witnessing the shooting death of her diplomat father seven years earlier. Her father's murder was never properly investigated and it remains unsolved. Kate's life is interrupted once more when she wakes up one night to the sound of the air raid alarm and the terror whistles of a bomb's stabilizers screaming toward the roof of her house. Kate survives, but she is injured. Her house is gone as well, and after her time in the hospital, Claire Giroux, a kind doctor and family friend, invites Kate to live with her as she recuperates. This arrangement works well for them until a few months later when Claire's husband comes home from the war. Within days the lives of both women are drastically altered, and events are set in motion, both in England and in Canada, that challenge Kate and Claire to their limits. The Orphan Girl is a moving and powerful story about friendship and courage, and about promises made and kept.