A group of people searching for "hidden treasure" end up far away from home when people start dying. They don't know what is happening until they go deep underground and they meet up with Alien and Predator, who both are doing the killings. Eventually the Alien and Predator start fighting for supremacy, while the humans sneak around trying not to get killed. At points it seemed like the Predator was protecting the humans. Eventually the humans are able to get out of the cave, and cause a big explosion to try to kill all the Aliens and Predator. Unfortunatly they were not entirely successful as with most movies, it seems to be setting up for a sequal.