In Lille, Claire Gauthier is an ordinary married woman with a young daughter that works in an insurance company analyzing losses of insured properties. When the single veterinary Laurent Kessler claims damage in his basement caused by a flooding due to water leakage, Claire resolves the situation favorably for him. The weird Laurent visits Claire in her office successively, inviting her for drinks and lunch, and they get close to each other. Meanwhile, a serial killer is terrorizing Lille,
