The story is set against the eerie backdrop of the Devonshire moors, where an ancient legend speaks of a monstrous, spectral black hound that has haunted the Baskerville family for generations. The recent, mysterious death of Sir Charles Baskerville, found dead on the moor with giant dog footprints nearby, brings the case to Sherlock Holmes and his companion Dr. Watson. 

Initially, Holmes and Watson dismiss the supernatural theories, but as the new heir, Sir Henry Baskerville, arrives from North America and receives dire warnings, the mystery deepens. Holmes sends Watson to the gloomy Baskerville Hall to investigate the local inhabitants and myths. The novel masterfully maintains tension between a rational explanation and a supernatural cause, leading readers through a complex plot with multiple suspects and red herrings until the final, satisfying reveal.