The story is about the Baskerville family

The story is about the Baskerville family ‘These papers were given to me by Sir Charles Baskerville，’said Dr Mortimer．‘He asked me to take good care of them．You may remember that Sir Charles died suddenly three months ago．His death caused much excite－ ment in Devonshire，the county where Baskerville Hall is．Sir Charles was a sensible man，but he believed the story which is told in these papers．’

Dr Mortimer went on：‘The story is about the Baskerville family．I have come to see you because I need your help．I think that something terrible is going to happen in the next twenty－ four hours．But you can't help me unless you know the story in these papers．May I read them to you？’‘Please continue，Dr Mortimer，’said Holmes，and sat back in his chair with his eyes shut．

Mortimer began to read in his high，rather strange，voice：William Baskerville，write this for my sons in the year 1742．My father told me about the Hound of the Baskervilles．He told me when it was first seen，and I be- lieve his story was true．I want you，my sons，to read this story carefully．I want you to know that God punishes those pead who do evil．But never forget that He will forgive those who are sorry for any evil they have done．