2019, Paris, at night, under Pont Alexandre 3, Maxime, eleven years old, is thinking of jumping into the Seine. A caped and masked woman, speaking English, stops him in his suicidal gesture and preaches to him. Maxime doesn't want to speak to her and flees from this strange character. But Marlène Superhero has a job to do. She won't leave without knowing why such a young teenager wants to die and how to help him. Maxime ends up admitting that he suffers from not being a Marine in the eyes of his parents who deny his transidentity. That night, Marlène saves Marine, or Marine saves Marlène.