High school is finally over. Brothers Josh and Ben, looking forward to their bright futures, throw a party in their family's survival bunker for their classmates. Things take a nuclear turn when war is declared and Josh, Ben, Camila, Saundra, Travis, Kit and Scott are trapped in the bunker. Attempts to communicate with the outside world are futile and supplies start to dwindle. The world may have ended outside but the tension is just getting started underground.