A deadly exotic poison drives men to madness in Cornwall's fog-shrouded landscape. Two brothers collapse into permanent insanity, their sister found dead after an ordinary evening of cards. When Holmes arrives, he uncovers a web of buried secrets: a murdered woman, a brother's brutal crime, and a lover's calculated revenge using a plant from distant shores. What follows is one of Holmes's most psychologically dark investigations, where the line between justice and vengeance blurs into something deeply unsettling. The detective must confront a killer whose motives are almost sympathetic, whose method is almost poetic in its terrible precision. This is Victorian mystery at its most atmospheric and morally ambiguous.
