On the early morning of March 11, 2008, television reporter Angela Vidal and her cameraman, Scott Percival, are assigned to follow firefighters Jake and Fletcher on their night shift. They are given a brief tour of the fire department, but an emergency call from an apartment building sends the crew out to investigate. When they arrive, the caller says that he and the other residents heard screams from an old woman who has locked herself in her apartment. The firemen, police officers, and camera crew go to the apartment, only to be attacked by the old woman, who becomes extremely aggressive and bites one of the policemen. Eventually, they are forced to kill her to stop her. As all the residents in the building head downstairs for safety, the team finds a second old woman similar to the first and bring her downstairs with the others.