A Private Affair (2002)

It's been six months since Rachel Siprien disappeared. At the request of Rachel's mother, private detective François takes over the investigation. The young woman, with a complex and multi-faceted personality, is part of a strange network made up of her best friend, her ex-boyfriend, her stepfather and everyone who knows her well or even slightly. François begins to frequent these various friends and acquaintances, and penetrates Rachel's daytime and nocturnal habitat. He spies, asks disturbing questions, and intentionally fills in the blanks left by those he questions.