Six years ago NASA discovered the possibility of alien life within our solar system. A probe was launched to collect samples, but crashed upon re-entry over Central America. Soon after, new life forms began to appear and grow. In an effort to stem the destruction that resulted, half of Mexico was quarantined as an infected zone. Today, the American and Mexican military still struggle to contain the massive creatures... A jaded US journalist (McNairy) begrudgingly agrees to find his boss' daughter, a shaken American tourist (Able) and escort her through the infected zone to the safety of the US border.