A Study in Grey, John Linwood Grant

 Amazon link
Number 4 from "The Science of Deduction" series my "Curious Case of the Clockwork Doll" appeared in.

I absolutely loved reading John Linwood Grant's Edwardian era mystery centering on Grant's own characters - Military Intelligence agent Captain Redvers Blake, Henry Dodgson, and Abigail Jessop - with Sherlock Holmes weaving in and out. There were clever, witty exchanges that made me laugh out loud, plot twists that surprised me, and a horrifying ending, with lots of great historical detail throughout - perfect!

I didn't want it to end because I liked these characters and this world so much with its Pendulum Club, London War Office, and creepy seance scenes.

I'm looking forward to reading more by this author.