In the remote recesses of Kentucky's ancient Labyrinth Cave, a treasure is hidden. It is known simply as Moon Rock 66095, but it holds world-changing scientific properties. Led by a murderous scientist, a group of escaped convicts has hijacked and brutalized an underground NASA training mission, forcing them to guide them to the prize.
As they descend into the endless, murky caverns, the authorities above ground desperately try to track them. The group's only chance for survival rests with cave researcher Whitney Burke, who has sworn never to enter the caves again -- but whose husband and daughter are now at the convicts' mercy. With a crack rescue team, she must face her worst fears and descend into the abyss to save her family -- before they are lost forever in the endless dark of the Labyrinth