A horrifically mutilated corpse is discovered wedged in an isolated crevice. The highly-regarded but unpredictable ex-commando Pierre Niémans is sent from Paris to the French Alps to investigate. Meanwhile, Karim Abdouf, a young Arab policeman, is trying to find out why the tomb of a young child has been desecrated.

When a second body is found, high up in a glacier, the paths of the two policemen are joined in their search for the killers, a trail that embroils them with the mysterious cult of the Crimson Rivers.