While pursuing an investigation police officer Alex is injured by a mysterious character with a disfigured face. Stuck in hospital, he meets Léo, an eleven-year-old patient who has the ability to leave his body at will. The boy can fly and pass through walls like a phantom, invisible to all. Thanks to Léo, Alex, along with the intrepid journalist Marie, can assume the roles of guardian angels. Alex and Marie are in love, but have not told one another. The disfigured gangster is threatening the city with a terrifying computer virus. Although the policeman is stuck in his wheelchair, the boy can go anywhere he chooses. Alex can continue his investigation, with Léo acting as his eyes and legs.