After a mass shooting, seven militiamen hide out in a lumber warehouse when they make a disturbing discovery: an AR-15 rifle is missing from their armory, and the model of this weapon is exactly the same as the one used by the rumored shooter. Fearing that the authorities have linked them to the shooting, the militiamen decide to find the mutineers in their ranks and hand them over to the police for their own safety. Former police officer Gannon is assigned to the case investigation team as a security investigator to prevent undercover police infiltration. However, a series of mysterious messages from nearby militias exacerbate the tension, and a larger conspiracy gradually surfaces...