'Nightline' Face-Off: Does Satan Exist?

The devil -- also known as Satan, Lucifer and Beelzebub -- has become the primary antagonist in almost every major religion. He is seen as the rebel, a serpent and a fallen angel who tempts mortals into committing sin, and preys upon their despair. But does Satan really exist? That question will be debated Friday, March 20, when "Nightline" tackles the controversial and sensitive issue in the third installment of the "Face-Off" series. The "Nightline Face-Off" launched two years ago by...Full Story