Alain, a former mountain guide, decides to change the course of his life to become a teacher. Facing a group of challengingly colourful teenagers, Alain struggles to stimulate them. In a teambuilding effort, he arranges a field trip to... the heart of a glacier! The breath-taking beauty of the icy caves leaves the students in awe. They return to class appalled by the idea that the glacier might disappear due to global warming. With the support and guidance of Alain, they embark on a crazy mission: prevent the glacier from melting... and nothing will stop them!