A film about a dream that, despite hundreds of theories, still remains an unsolved mystery. The largest scientists, physiologists, neurobiologists, and somnologists are struggling with his riddle. “Whoever discovers the secret of sleep will know the secret of the brain,” said the brilliant French scientist, neurophysiologist Michel Jouvet, one of the founders of somnology, the science of sleep. It turned out that being in a dream is not at all a harmless activity. Our life and health directly depends on what happens to us during sleep and in our dreams.