Aurelio is an impoverished, unlicensed dentist and working-class man in a small, oppressive town. Operating out of an antiquated and decrepit office, he is a man of precise, controlled habits who maintains a cool demeanor even under the threat of violence. Despite his lack of formal education and low social standing, he holds a quiet disdain for the town's corrupt leadership and remains unintimidated by authority.

The Mayor is the unnamed authoritarian ruler of the small town who maintains his control through fear and corruption. Suffering from an infected tooth and an abscess, he arrives at the dentist's office with a swollen cheek and a half-shaved face. His intense physical pain temporarily strips him of his usual dominance, forcing him to submit to a working-class man he normally rules over.

Aurelio's 11-year-old son serves as a naive mediator between his father and the dangerous local authority. Speaking in a shrill voice, he talks to his father from a distance, never entering the workspace but sharing the waiting area with the Mayor. He announces violent threats with a matter-of-fact tone, showing how accustomed he is to the fear and instability of his community.