He's called 'the monster of the Bastille'. He's brutally murdered 27 elderly women in one area of Paris. Chief Inspector Morvan is in charge of the investigation into this macabre and sinister case: every victim seems to have invited the killer into her home, to have enjoyed a meal, even celebrated, before her death. And each time the killer has meticulously bathed himself, leaving the scene of the crime without a single fingerprint. In Argentina meanwhile, an untitled manuscript by an unnamed author is discovered amongst the papers of a missing poet, known for his hatred of the novel. The Investigation seeks to unravel two cases - one criminal, one literary. Part police investigation, part historical account and part novel, it shows Saer at his virtuoso best, effortlessly orchestrating the different layers.