Based on a real event, twelve dead bodies are found in the Tula River, we see the events that lead up to the massacre in a tale of crime, vice, corruption and sleaze.
Two students want to interview young drug addicts. A gang member robs his equipment, cameras and recorders; to reclaim them, they must become acquainted with the band of "Los Chuchos". The drug dealer of the band decides to be in charge of them. He rapes the young student and is willing to kill his companion.
The dead body of a young man who was kidnapped is found, the police looks for the kidnappers as a web of corruption its uncovered in the police department.
