-A summer evening. Marc is playing hide-and-seek with his best friend Julien and his little brother Gabriel. This game of hide-and-seek proves fatal for young Gabriel, who disappears without a trace. This tragedy led to the breakup of the family and Julie's departure. From that day on, Marc, who still lives with his mother Micheline, devotes his time to ufology (the study of UFOs and UFO-related phenomena) in an attempt to shed light on Gabriel's disappearance. Fifteen years later, in concert development, Marc is on the verge of giving up when he receives an anonymous note that seems to put him on the trail of his brother. With Julien back in his life, he tries to find answers to his questions.