Author: Bonnie MacBirdCrime & mystery | Espionage & spy thrillerPublished on 1st January 2026 by HarperCollins Publishers (Collins Crime Club) in the United Kingdom as part of the 'A Sherlock Holmes Adventure' series.Paperback / softback | 384 pages 197mm x 130mm x 25mm | 266g Holmes and Watson face treachery and danger in the latest full-length thriller by Bonnie MacBird, author of the bestselling Sherlock Holmes novel Art in the Blood. Murder, jealousy, and deceit underscore three interlocking mysteries as Holmes and Watson take on a high profile case at Windsor Castle, a boy drowned in the Serpentine, and a crusading women’s rights activist who suspects a traitor in her organization. The cases send them into danger into locales as varied as the Palace itself, a dockland cannery, an arts and crafts atelier, and a Gypsy encampment. But is there peril underfoot as well – right at 221B Baker Street? The twisting, breathlessly plotted conjoined mysteries that Bonnie MacBird is known for provide a thrill ride that will delight Sherlockians worldwide.
