After the corrupt former Mayor is killed by the peasants, poor janitor Juan Vargas is appointed new Mayor of a desert town in central Mexico. Although he tries to bring the motto of the ruling party to town (modernity, peace and progress) he realizes soon that there's nothing to do against corruption... except to become corrupt. Step by step, helped by his pistol, Juan Vargas becomes the law and the worst Major in the town's history.　　
　　故事讲述墨西哥农民杀死腐败的前市长后，不幸的看门人阿瓦尔加斯在墨西哥中部被任命为一个沙漠镇的新市长，他努力提倡执政党的新意识，到任不久就立下反对腐败的座右铭，但反对也开始变得腐败，一步步在他的枪手帮助下，阿瓦尔加斯成为法郎和镇上历史最恶劣的一页。