Long before it was a sugary moviefest, the Halloween we know was called Samhain. The Celts of ancient Ireland believed Samhain was a night when the barrier between worlds was thin, the dead could cross over, and if you didn't disguise yourself, evil fairies might spirit you away. Over time the holiday shape-shifted too, thanks to the Catholic Church, pagan groups, and even the brewing company Coors. From the Great Famine of Ireland to Elvira and the Simpsons, we present the many faces of Halloween.