For years, there have been documented cases of UFO sightings around the world - Buenos Aires, Seoul, France. But in 2011, these sightings will become a terrifying reality when Earth is attacked by unknown forces. As people everywhere watch the world's great cities fall, Los Angeles becomes the last stand for mankind in a battle no one expected. It's up to a Marine staff sergeant and his new platoon to draw a line in the sand as they take on an enemy unlike any they've ever encountered before.