Americans Ben and Sean (Max Minghella and Emile Hirsch) travel to Moscow to sell their social networking/party locating software. As they approach the airport, their plane short circuits due to an electrical storm but regains power. After arriving, they find their Swedish business partner, Skyler (Joel Kinnaman), has betrayed them and already made a deal with the Russians, using a knockoff application. They go to a nightclub and meet Natalie (Olivia Thirlby), an American, and her Australian friend Anne (Rachael Taylor). The lights go out in the club and everyone heads outside. There, they witness what appears to be an Aurora (astronomy). Balls of light fall from the sky and then fade away. When a policeman investigates he is quickly disintegrated. The invisible entities begin hunting and killing people, sending them into a panic.