or what was responsible for the death of diana? >> the french investigation finds that the driver, henri paul, was speeding and intoxicated, deeming him solely responsible for the accident. the photographers are cleared and the case is closed. but for years afterwards, conspiracy theories linger, especially with dodi's father, mohamed al fayed. >> mohammed believes and will always believe that his son and the family's very dear friend, diana, princess of wales, were murdered. >> when we come back, an alarming new piece of evidence. >> i have a letter which says, the next few months are the most difficult of my life, i fear i'm going to be killed in an automobile accident. (burke) vengeful vermin.