Fifteen-year-old Efraín and his two younger brothers live in a house on the hillside in Monterrey, Northern Mexico. They are left to fend for themselves after their mother is wrongly arrested for theft. Má has raised her boys to keep out of trouble with the local gangs and to study for their future, but they are viewed by society as good-for-nothings or criminals simply because of where they live. The only people offering any kind of support are the local gang members - but everything comes with a price tag