"The story got more and more scary. I guessed who did it but not how or why." Grace 9

Upon the ground around the body were the footprints of a gigantic hound.
When Sir Charles Baskerville is found dead his face distorted with shock and horror Sherlock Holmes and Dr Watson are faced with a sinister and difficult puzzle.
A fearsome creature stalks the wild and barren hills of Dartmoor. Is it a demon from the spirit world? Will it defeat their skill and courage?
Who is the tall mysterious figure seen lurking on the moor at night?
Can Holmes save Sir Henry the new owner of Baskerville Hall from the ancient family curse? Or will the terrifying hound claim yet another victim?