Lise Stocker and Clovis Bouvier face a totally new threat. A virus is spreading in Annecy. A race against the clock is committed to find the origin of this virus and try to stop its spread. Is it an accident? A criminal act? Terrorist? Does this virus have a connection with the mysterious disappearance of a little girl and her father? Every minute counts because already the number of victims increases ... Spin-off from "Vanished by the Lake" and "Killer by the Lake".