On the morning of Christmas Eve a terrorist sets off an explosion that rocks the Federal building and unleashes a toxic gas throughout the ventilation system. His purpose - to expose the Government's secret biological warfare weapon, a deadly virus that instantly attacks a person's adrenal system, causing them to become inhumanly aggressive, with an uncontrollable urge to kill each other. Now everyone below the 6th floor is infected in order to contain the situation, the Federal Government places the building on lockdown mode, which automatically initiates a countdown that will detonate the building and bury the survivors and their secret inside. With the time bomb ticking, a group of uninfected employees must band together and fight to get out of the building alive. But they quickly realize there might be no escape, as whatever happened in this building is not intended to get out.