The tragic death of a railway magnate in a sleazy brothel has shocked high society. Meanwhile, private investigator William Monk acquires a mysterious new client who asks him to ascertain beyond the shadow of a doubt whether or not her fiancé, a railway-firm executive, has become enmeshed in fraudulent practices. And so Monk embarks upon a journey that will revive memories stripped from his consciousness by amnesia—as a past almost impossible to bear returns, eerily paralleling a fresh tragedy that has already begun its inexorable unfolding.