The Question and Answer section for The Hound of the Baskervilles is a great resource to ask questions, find answers, and discuss the novel.
The Baskerville heirs die under questionable and mysterious circumstances.
Watson and Holmes hear the hound howling on the moor. They see a body fall from above and discover it to be none other than Sir Henry..... dead.
Holmes was expecting Sir Henry to appear. Unfortunately the hound appears soon after.