Mary Russell and Sherlock Holmes, hoping for a respite in the French countryside, are instead caught up in a case that turns both bewildering and intensely personal

After their recent adventures in Transylvania, Russell and Holmes look forward to spending time with Holmes’ son, the famous artist Damian Adler, and his family. But when they arrive at Damian’s house, they discover that the Adlers have fled from a mysterious threat.

Holmes rushes after Damian while Russell, slowed down by a recent injury, stays behind to search the empty house. In Damian’s studio, she discovers four crates packed with memorabilia related to Holmes’ grand-uncle, the artist Horace Vernet. It’s an odd mix of treasures and clutter, including a tarnished silver lamp with a rotating shade: an antique yet sophisticated form of zoetrope, fitted with strips of paper whose images dance with the lantern’s spin.