Six years ago, NASA observed extraterrestrial civilizations, but the spacecraft sent out for survey crashed in Mexico on its return. Since then, many areas in Mexico have been infected by mysterious alien creatures, and countless people have died. The United States sent troops to fight against the huge alien monsters, and both sides suffered heavy casualties. Los Angeles reporter Andre Carter (Scott McNairy) accepted a request from a wealthy man to go to the infected area in Mexico to find his daughter Samantha Winden (Whitney Able). Andre successfully met Samantha, and the two immediately boarded a train to the United States, but the train turned back halfway. They were forced to find other ways to return home, but fate was unpredictable, and the road back home seemed full of obstacles. Helplessly, Andre and Samantha had to walk through the dangerous infected area...