Aimee's childhood friend, Laure, is a policewoman. Her partner, Jacques, has set up a meeting in Montmartre with an informer. When Laure reluctantly goes along as backup, Jacques is lured to an icy rooftop, where he is shot to death. Laure's gun has been fired, gunpowder residue is found on her hands, and she is charged with her partner's murder. The police close ranks against the alleged cop killer. Aimee is determined to clear Laure. In doing so, she encounters separatist terrorists, Montmartre prostitutes, a surrealist painter's stepdaughter, a crooked Corsican bar owner, and learns of "Big Ears" - the French "ear in the sky" that records telephonic and electronic communications - which the Security Services monitor. Identifying Jacques' murderer brings her closer to solving her own father's death in an explosion in the Place Vendome years earlier. It still haunts her. She cannot rest until she finds out who was responsible.