A teletype message flashes across the screen... : Master Sergeant Larry McRose, U.S. Army, Frankfurt, West Germany : Report to Zombie Unit, El Paso, Texas At El Paso airport five U.S. Army sergeants meet up with Major Paul Hackett , the leader of the Zombie Unit. The unit is composed of soldiers reported to be killed, and are on temporary assignment under Hackett for this mission. Jack Benteen  is a tough Texas Ranger, his best friend from high school is Cash Bailey , an American and former police informer who has crossed into Mexico and become a major drug trafficker. A D.E.A. agent and several soldiers from the clandestine U.S. Army unit show up in town, who are also tracking Cash Bailey. When the soldiers rob a local bank to get Bailey's money and a cash deposit box that contains accounts on the drug money he's deposited there, one of the soldiers is killed and two others are captured by Benteen and placed in the town Jail. Benteen is confronted by the D.E.A agent who turns out to be their commanding officer and reveals their true mission to him to obtain their release. Now knowing the full story, Benteen joins with the soldiers and crosses the border into Mexico to track down Bailey and end his drug running. At Bailey's Hacienda Benteen's girlfriend Sarita , who was once Bailey's girlfriend, has crossed into Mexico to join him after arguing with Benteen. At a huge Independence Day festival Benteen confronts Bailey while the soldiers attack Bailey's private army. McRose witnesses Hackett shooting Bailey's accountant and at the same time revealing himself to be Bailey's partner. The town erupts into a huge gunfight and at the end of the movie few but Benteen and Sarita survive, to ride off into the sunset together.