When Sir Charles Baskerville dies in mysterious circumstances, his nephew and heir Sir Henry returns from South Africa. In the meanwhile, Dr. Mortimer, the local doctor, is concerned about Sir Henry's safety, so he consults Sherlock Holmes and recounts the tale of one Sir Hugo Baskerville, who several generations previously, had been killed by a huge hound and which now is believed to be a curse on the family. When Holmes agrees to take on the case it almost immediately becomes apparent that Sir Henry's life is indeed in danger.