Two years after the occupation of Earth by aliens, a group of survivors located in Australia continue to fight for their survival. When rumors spread of an ancient alien weapon known as Rainfall that might help humanity survive their oppressors, the survivors send Matt Simmons and his alien ally, Gary, to the former Pine Gap U.S. military base to learn the truth. Simmons and Gary must cross enemy lines to reach their objective as quickly as possible. As the evil alien occupiers take more ground with every passing day and the number of casualties among humans and their allies increases, Rainfall is the only hope left for winning the war and reclaiming the Earth.