Once Upon a Time in Mexico (2003)

The film is based on the story of a drug lord Barrillo, who pretends to overthrow the Mexican president. Within the drama, another of the principal persons is a corrupt CIA agent Sands who at that time, demands retribution from his worst enemy in order to carry out the drug lord's uprising against the government. Mariachi is recruited by Sands to take out Gen. Marquez (has a huge score to settle with the Mariachi), who has major beef with Mariachi to begin with. He sends Cucuy (the muscle for Sands) to shadow and keep tabs on the Mariachi. Marquez is working with Barrillo, and is about to assassinate El Presidente and assume power. Sands also convinces Jorge Ramirez (retired-FBI, has old scores to settle with Barrillo) to come out of retirement and take out Barrillo and Dr. Guevera (personal Dr. to Barrillo, killed Jorge's partner a long time ago), who brutally tortured and killed Ramirez' FBI partner.