London edition (Hodder and Stoughton) has title: The Chameleon.

Release date is 2025-12-01

an anonymous Project Gutenberg volunteer

Poison shadows by William Le Queux is a mystery novel written in the early 20th century. It follows Sibell Dare, a young heiress pressured by her scheming aunt, Lady Wyndcliffe, and her guardian to marry for money, even as she loves the capable but penniless Dr. Brinsley Otway. When Sibell unexpectedly inherits a fortune on condition she live in the long-shuttered Guest House at Hampton Court—an old Tudor residence shadowed by sudden deaths—eerie signs and unexplained illnesses blur the line between poison plot and haunting. The atmosphere mixes high-society manipulation, gambling and blackmail with a creeping, possibly scientific, menace.

The opening of the novel sets the stakes and the mystery: at a Belgian seaside resort, Sibell’s aunt and guardian coldly plan to sell her into marriage with rich Gussie Gretton, but Sibell refuses, devoted to Otway. Back in England she learns she has inherited her uncle’s wealth if she reopens and resides in the Guest House, a storied place linked to abrupt deaths; a local antiquary confirms the legends, and when agents force the door, an auctioneer collapses with a sudden heart seizure in the great room. A constable later reports seeing a fleeting dull green light within the locked house. Sibell tours the dust-choked rooms with Otway, who discovers rare books on poisons, then collapses that night after biting a peach she sent—yet expert analysis finds no toxin, and doctors waver between mysterious poisoning and heart failure as he hovers near death before slowly improving. Meanwhile, Lady Wyndcliffe, plotting a Riviera escape and debating inviting Otway, reveals to her domineering butler-confidant a dangerous secret past and fear of a man named Rupert, hinting that the social intrigue around Sibell is entangled with deeper, darker designs. (This is an automatically generated summary.)

Originally published: New York: The Macaulay Company, 1927