The Adventure of the Engineer’s Thumb by Arthur Conan Doyle

A young hydraulic engineer is lured to a mysterious country house for a job and narrowly escapes with his life—and without his thumb—after discovering a secret counterfeiting operation. He turns to Holmes, who investigates the case and traces the criminals, though they ultimately escape. The plot is more action-packed than most Holmes stories, with physical danger and suspense. It highlights Holmes’s bravery as well as his intellect. A gripping, fast-paced tale of deception and violence.