In a tense opening set in a dim office, a man hurriedly stuffs bags of money and vanishes into the night, leaving behind a recently killed man. A furious peasant mob closes in and executes the fleeing figure with a machete, revealing that the dead man was the mayor of San Pedro de los Saguaros. In the wake of this political bloodshed, State Governor Sánchez of the PRI orders his Secretary López to appoint an interim successor who can shore up the party’s image ahead of the upcoming general elections. López delegates the task to his subordinate Ramírez, who quickly proposes Juan Vargas, Damián Alcázar, a well-meaning but dimwitted head of a landfill, as the town’s temporary ruler.
Juan Vargas, Damián Alcázar, and his wife Gloria, Leticia Huijara, arrive to San Pedro with bright hopes. They are confronted by stark poverty and a community where many residents remain illiterate and some still speak little or no Spanish. Despite the initial dismay, Vargas decides to stay and see what his new post might bring, buoyed by a sense of possibility and ambition. He is soon accompanied by his sharp secretary, Pek, Noemí García, as he begins to meet the town’s notables and assess the corruption that previous PRI administrations allegedly siphoned from the coffers.
The town’s landscape is crowded with characters who shape Vargas’s uncertain path: Doña Lupe, the shrewd madam of the local brothel; Pérez, a greedy parish priest; and Doctor Morales, an educated physician aligned with the opposition PAN. Vargas travels to the state capital to request more funding, but when his car breaks down, an American named Robert Smith offers help under a false name and address, leaving Vargas with a revolver and a copy of the Constitution. López initially denies the larger ask for funds but can’t resist arming Vargas with the tools—literally and legally—that could transform his rule.
Back in San Pedro, Vargas digs into the Constitution to uncover ways to leverage fines and taxes as tools of governance—some legitimate, others ethically dubious. He confronts the brothel head-on, only to be met by Doña Lupe’s cleaver. In a tense exchange, Vargas shoots her in the leg and bolts for safety, a reckless decision that seeds his moral unraveling. Doña Lupe reappears later, offering a hefty bribe to look the other way while she operates, and Vargas, hungry for power, pockets the money. From that moment, his discipline erodes as he revels in his new authority.
To solidify his grip, Vargas introduces Smith as an American engineer tasked with bringing electric lighting to the town, promising a 50-50 partnership. He lodges Smith at his own home, deepening his contamination by corrupt influence. Doña Lupe, fed up with Vargas’s increasing demands and the removal of her influence, hires a brutal bouncer who beats Vargas in a confrontation. Vargas responds with a brutal ambush, killing both the bouncer and Doña Lupe and leaving behind his PRI pin at the crime scene, a telltale symbol of his fall from integrity.
The next morning brings fresh trouble: Vargas discovers his pin is missing and chooses to frame Filemón, the town drunk, with the help of a manipulated narrative that implicates Doctor Morales as the mastermind behind the crime. Morales is exiled on spurious charges—partly genuine, partly sensationalized—and Filemón is moved toward jail. During the process, Vargas learns Filemón had found the missing pin at the ravine, and, in a chilling turn, he executes Filemón to silence him for good.
Returning to the town, Vargas finds his wife Gloria entangled with Smith, and the sight of their betrayal drives him into a furious, controlling rage. He chains Gloria at home and spends more and more on punitive taxes and fines, treating the town’s residents as subjects of his new regime. Pek publicly denounces Vargas as “the worst municipal president the town has ever had,” and López arrives in San Pedro in retreat, having survived a failed attempt to kill a political rival and now demanding the money Vargas has generated.
The situation climaxes when Gloria escapes with Smith to the United States, taking Vargas’s money with her. The collapse of Vargas’s moral fortress comes swiftly: he kills López and his henchman Tiburón, and he faces a furious crowd led by Father Pérez and Pek. The townspeople nearly lynch him, but government officials intervene, resettling the hunt for López and rescuing Vargas from mob justice.
In the film’s final turn, Vargas reappears on a national stage as a Federal Deputy, presenting himself as the man who toppled López and delivered justice. Ramírez, who had once helped Vargas, becomes administrator at the landfill where Vargas began his political ascent, while a new mayor arrives to San Pedro de los Saguaros—mirroring the arrival that opened the story and signaling that power, once set in motion, can recreate itself in its own image.
