A horrific discovery in a small town nestled high in the French Pyrenees begins to unravel a dark mystery that has been hidden for years. On an unforgiving winter morning, a group of workers discover the headless body of a horse, hanging suspended from the edge of a frozen cliff. Commandant Martin Servaz starts investigating and soon discovers a dark story of madness and revenge.

The economic situation is a nightmare: only 20% of the population is employed. The Actives live inside the city. On the fringes, in the Zone, live the Jobless. Separating them is a wall.