 Five miles below the Earth s surface, a group of scientists is working in self-imposed isolation, perfecting a series of DNA experiments that could literally change the world. But when one of those experiments goes awry, it unleashes a nearly immortal organism--one capable of instant regeneration, and with an insatiable appetite for living flesh. Soon, nothing can contain the creature, and with the lab s life support systems quickly shutting down, the scientists grimly prepare for their final battle...