In the basement of a large Victorian house in London, Charles Cleasby painstakingly re-enacts the great sea battles of his hero, Horatio Nelson. He is also writing a faithful biography of the great man, as a true English hero for an age without idols, a 'bright angel' to Charles's dark shadow. But as Charles's visiting typist, Miss Lily, begins to question Nelson's heroism, and as Charles unearths evidence which tarnishes the image of his icon, his own precarious sense of identity is undermined and the battle raging inside him -- between darkness and light, reality and fantasy -- threatens to overwhelm him.