ATF: In the wake of the tragic events at Waco, Texas where an armed conflict with armed militiamen broke out, agents of the federal government's Alcohol, Tobacco, and Firearms (ATF) carry out a clandestine mission within another militia operation that is possibly involved in the sales of guns and the murder of an agent. Agent Robin O'Brien infiltrates the operation against her director's orders. When events start unraveling and an FBI agent threatens to take over the operation and start a military action, the ATF agents have to apply what they learned from Waco to save another blood bath.