"Last of the cowboys" Jeb Maynard (Charles Bronson) runs the U.S. Border Patrol in La Mesa, California. Every day illegal aliens attempt to escape from poverty for a "new life" in the United States. Most are victims of "polleros", unscrupulous smugglers who exploit them at every turn. When one of these, Hotchkiss (Ed Harris), murders Jeb's colleague Scooter (A. Wilford Brimley) and a young Mexican boy, Jeb is determined to track the killers down. With the help of Elena (Karmin Murcelo), the boy's mother and rookie patrolman Jimmy (Bruno Kirby), Jeb must contend with the FBI and expose the deadly trade in human contraband.