A young man at twenty narrates the early episodes that establish him as a cunning and audacious figure: secret keys and hidden letters expose a plot of abduction and a clandestine tribunal aimed at silencing an enigmatic woman tied to an ancestral conspiracy. He moves through jealous rivals, nocturnal entries, and clashes with persistent detectives while unraveling puzzles involving a mutilated hand, a seven-branched candlestick, a ruined estate, and an isolated lighthouse. The narrative alternates tense set pieces of pursuit and theft with reflections on genius and madness, building to a personal confrontation that mixes passion, revenge, and long-buried family revelations.