After months have passed without an arrest in her daughter's murder case, Mildred Hayes places three huge signs leading into her town with a message for Willoughby, the town's respected Chief of Police, which annoys the citizens of Ebbing very much. A dentist files a complaint, and after that Mildred makes an appointment with him.

She sits in the dental chair and points to her mandible: 'I don't know what it is. It feels like it is kind'a waggling'. Without a look at the oral cavity, the dentist concludes: 'Well if it is waggling, it's gonna have to come out'. Mildred asks whether the dentist should not have a look at it first. The dentist glances at her mouth and repeats that the tooth has to come out. When he starts his drill, Mildred asks: 'Can I get a little novocaine there, doc?' The dentist applies infiltration anaesthesia and says 'Give it a couple of minutes' and takes a look at his watch. After some time, the dentist grabs his drill again. While the drill approaches Mildred, he tells her that the Chief of Police has a lot of friends who are not very pleased with her actions.

Mildred grabs the hand with the drill and she brings the whirring drill towards the thumbnail of the dentist. Slowly, the drill whirs into the nail and underlying flesh. Groaning with pain, the dentist sits on the floor. Mildred rinses her mouth with water, spits this on the dentist and tells him that good friends should tell the Chief of Police to do his job.

Later that day, the Chief of Police arrives at the gift shop where Mildred works and asks: 'you didn't happen to pay a visit to the dentist today, did you?' Unintelligible, since her mouth is still anaesthetised, Mildred denies it. Despite her denial, she is taken to the police station. When she is interrogated she explains that the dentist's hand slipped and he drilled a hole in his own. Smiling, Mildred concludes that it is his word against hers. The Chief of Police says: 'Do you think I care about the dentist? I don't care about dentists. Nobody cares about dentists'. A few moments later, the Chief of Police collapses and is taken to a hospital. Mildred is released and continues to challenge the police.