Many serial killers were more brutal. Others slaughtered more often. But Jack the Ripper remains the world's most infamous murderer. In 1888, he slashed his way across London and into the annals of crime when he murdered and mutilated even women. His ghastly rampage remains one of history's great mysteries. Who was this butcher that baffled Scotland Yard's best minds? Today's foremost Ripper experts offer insights into the madman's mind and theories of who he really was.