The story follows Angela Vidal, a young television reporter, and her cameraman Scott, who are covering the night shift at a Los Angeles fire station for a TV show. They accompany the firefighters on a routine emergency call to an apartment building, but once inside, they discover something far more horrifying.

Soon after their arrival, the building is sealed off by the CDC, and no one is allowed to leave. It becomes clear that a deadly virus is spreading — one that turns people into violent, rabid killers. The residents, including the news crew, firefighters, and tenants, must struggle to survive as they try to uncover the source of the infection.

The entire film is presented through the lens of the cameraman’s footage, giving it a raw, realistic, and claustrophobic tone.