Years after an alien invasion nearly extinguished the human race, three soldiers who survived on a secret moon base are sent to Earth to liberate the survivors from the Sentinel and its army and reclaim Earth at any cost.

A monster stalks the corridors of an abandoned mansion, targeting those curious enough to find themselves inside. Two friends break in and discover that all exits have been sealed off. The creature that hunts them is growing hungry for their blood and there is no escape…