The Sign of Four Spirits: A Sherlock Holmes Bookshop Mystery

Delany’s ninth mystery featuring Cape Cod bookstore owner and amateur sleuth Gemma Doyle (after 2023’s The Game Is a Footnote) is the series’ best yet. London, Mass., is hosting a new psychic fair that has attracted many visitors to the town, and to the Sherlock Holmes Bookshop and Emporium. During the event, Doyle is invited by her friend, Bunny, a former teenage pop star whose daughter, Ashleigh, assists Doyle in running the store, to a séance held by a medium named Madame Lavalier. Despite Doyle’s skepticism about the supernatural, she agrees to attend. When she joins the small gathering, however, Madame Lavalier excludes Doyle from the locked library where the group will attempt to contact the dead, citing the bookseller’s skepticism. The evening ends tragically, when one of the 12 people in the room is killed by a hatpin inserted precisely at the base of their skull. After elbowing her way into the police inquiry, Doyle utilizes her Sherlockian attention to detail to crack the case. The closed-circle setup is brilliantly executed, and will appeal to golden age mystery fans and Holmes fans alike. Delany’s series has plenty of gas left in the tank. Agent: Kimberly Lionetti, BookEnds Literary. (Jan.)