Private Investigator Aimée Leduc has been trying to slow down her hectic lifestyle—she's five months' pregnant and has the baby's wellbeing to think about now. But then disaster strikes close to home. A serial rapist has been terrorizing Paris's Pigalle neighborhood, following teenage girls home and attacking them in their own houses. It is sad and frightening but has nothing to do with Aimée—until Zazie, the 13-year-old daughter of the proprietor of Aimée's favorite café, disappears. The police aren't mobilizing quickly enough, and when Zazie's desperate parents approach Aimée for help, she knows she couldn't say no even if she wanted to.