Pays de Gex, on the Swiss border. P.A. and his group of friends are in their last year of high school. One hundred metres beneath their feet, the LHC, the most powerful particle accelerator in the world, recreates the energy conditions of the big bang in order to detect unknown particles. As winter sets in, P.A. starts to observe strange phenomena in the environment. The changes are imperceptible at first, but gradually his whole world seems to be on the brink.