After a fox drops a woman's severed hand in Whitechapel DI Mina Norroy arrives from Richmond, where the rest of the torso has floated down river. The woman was poisoned and then dismembered. Ella Bowe, missing from home for six months, seems a likely victim but is proved not to be. The police locate the fox, following it to the garden of the heavily booby-trapped house of weird reclusive Adelina Grace. A woman's foot is in the garden and Adelina's dead husband's body is inside the house, but he was not murdered, and none of the potions Adelina makes can be identified as the fatal poison. Then another woman's foot is found.