The wolf patrol finds itself on the site of their last scout camp. Where Ludovic, the new boy, had disappeared twenty years earlier. They have all gathered in the middle of this Ardennes forest because Etienne aka "Buffalo" sees an evil giant rat. And to make it disappear, his shrink had the good idea to undertake a kind of group therapy. Because apparently, this bad rat would have a link with the scout who disappeared - But everything will go to hell when at the bottom of their toilets, they will discover a temporal passage.