The Mer de Glace in Chamonix, November 86: every summer the meltwater that runs on the surface of the glacier flows into a huge crevasse called "a mill". In 1897, Joseph VALLOT had explored it to a depth of 60m, a lake had prevented him from going any further. Since then no one had descended into this well. In the fall, a multidisciplinary team made up of mountaineers including Jean Marc BOIVIN, speleologists and scientists descending into the crevasse... Superb images and live comments in a temperature of 0° and a humidity of 100%. The team reached 110m deep under the ice, a world first in glacier exploration. Jean marc BOIVIN seems delighted with his first speleological exploration. With the participation of Serge AVIOTTE, Jean Michel ASSELIN, Jean Marc BOIVIN, Janot LAMBERTON, Pierrot PILLET, Louis REYNAUD, Jean Luc RIGAUD and Denis TERMIER.

Greenland, the largest island in the world, is unlike any other country. The film recounts the exploration of the Inlandis cavities in Greenland during the summer of 1992. Janot Lamberton, one of the pioneers of these expeditions, ventured, with speleologists and mountaineers, into the moulins, these immense crevasses that tear through the back of the Inlandis, a vast glacier four times the size of France, while glaciologist Louis Reynaut studies infraglacial phenomena. It is obviously not easy to penetrate the depths of the ice and film at a depth of 150 meters in sub-zero temperatures. The light is blue in one of the most fascinating landscapes on the planet, where scientists and explorers collaborate to deepen their knowledge of the Earth.