After barely surviving a hostile invasion from an unknown alien species, mankind’s military powers joined forces to form the United Defence Force in a bid for survival. A decade later and the UDF has managed to force the enemy back to a final pocket of resistance in Pakistan patrolled by the soldiers based at Outpost 37. The world has long presumed that the war is over but little do they know that the aliens are planning a second attack, one the human race will not survive, and the handful of men left at Outpost 37 are all that stands between them and total annihilation.