When 14-year-old Jessica Grémard fails to return home, her desperate father begins a frantic search that leads him to a nearby stream. What he discovers there sets off a harrowing investigation by the Montreal Police, who must navigate the challenges of an outdoor crime scene where nature itself seems to be working against them. As detectives Johanne Bérubé and France Gignac meticulously piece together the evidence, they are forced to confront the chilling possibility that they are hunting a calculated predator who uses water to erase his tracks, turning a quiet suburban community into a landscape of fear and uncertainty.