Neighbors in an apartment block awake to find their doors and windows completely sealed shut. When strangers in hazmat suits infiltrate their building and begin snatching residents, tempers fray and fear takes over. In order to survive the residents mustidentify who the enemy is. But they soon discover that the real danger is already inside with them As a deadly virus of unknown origin sweeps through the building, the neighbors realize that breathing the same air is all it takes for the disease to spread. Unable to identify the infected from the uninfected, the quarantined start questioning the authorities. Loyalties are tested to their limits as friends and families turn against each other in an adrenaline-fueled fight for survival.