Aimée Leduc has always sworn she would stick to tech investigation--no criminal cases for her. Especially since her father, the late police detective, was killed in the line of duty. But when an elderly Jewish man approaches Aimée with a top-secret decoding job on behalf of a woman in his synagogue, Aimée unwittingly takes on more than she is expecting. She drops off her findings at her client's house in the Marais, Paris's historic Jewish quarter, and finds the woman strangled, a swastika carved on her forehead. With the help of her partner, René, Aimée sets out to solve this horrendous murder, but finds herself in an increasingly dangerous web of ancient secrets and buried war crimes.