Sean Vetter and Demetrius Hicks, who are former criminals, are members of the U.S. Drug Enforcement Administration working on the California/Mexico border. After arresting a drug baron named Memo Lucero, the mysterious "Diablo" starts to take over Memo's drug pipeline and territory, and to send a warning message to the DEA, organizes the assassination of Vetter. The assassination is botched and Vetter survives, but his wife, Stacy, is killed in the crossfire.