Mordock's cave is one of the spectacular wonders of the world... a place where sightseers can take a ride deep beneath the earth's surface to marvel at Nature's handiwork. But the darkness is also the home of things Nature never intended--things violent, bestial, and horrific... Now a sudden power failure has trapped a group of tourists in the underground depths. Their only escape route is through a sealed-off wall. But what lurks on the other side is something terrifying beyond belief--an obscene, living evil that has been waiting all these years to be set free...