For many shows, from thrillers to dramas, mystery is just one force keeping the audience interested. In Noah Hawley’s Legion, however, uncertainty is the foundation on which the rest of the story’s world is created. Its narrative is as unreliable as the broken mind of its protagonist, David Haller, played by Dan Stevens. Legion’s wildly inventive first season followed David, diagnosed as a paranoid schizophrenic, as he battled for control of his mind and explored his unknown, seemingly unlimited power. Technically, Legion is a superhero show.