1978. Didier Mathure, a brilliant space engineer, sees his dream go up in smoke when his rocket explodes during takeoff. Just when he thought he had hit rock bottom, he is transferred to the head of an investigation office specialized in UFOs and managed by a team that gives the impression of living on another planet. His mission: to find scientific explanations for the flying saucer sightings that are in the news. A real hell for this inveterate Cartesian who has only one idea in mind: to get out of there as soon as possible. But an extraordinary event will upset his certainties and open the doors to a world where nothing is impossible.