In any single family, grouping of people, society or religion, there is a code of conduct, a set of rules, a system, a “local” jargon, a way of functioning, a God even, that are unique. In Lanthimos’ film, the central symbol / myth (God?) is the canine tooth (hence "Dogtooth"), the fall of which marks the passage into adulthood. Until that critical moment comes, the children of the family are supposed to undergo a thorough education, which should equip them with all the necessary means to face the tough realities of life “out there in the wilderness”. The demonization of “the world out there” is used to justify the whole way the system within the family house walls functions.
There is a natural leader, the “caring father”, whose commands constitute the body of law that every child must obey, “in its own interest” and “in the global interests of the family”. There is a (relatively) passive mother, whose central function seems to be to confirm anything the father says, but whose potential to procreate also serves as an instrument of blackmail, by menacing the children that if they are not “good”, they will get more brothers and sisters and will have to share their rooms and favorite objects with them!
And then there are the children, two daughters and a son (plus an invisible son!), who not only constitute the embodiment of the parents’ fantasies, but also their guinea pigs – the very subjects of the parents’ experiment. Their acts of obedience are duly rewarded and any deviation from the rules on their behalf is firmly and severely punished. Everything they do or say is more or less either good or bad. But one shouldn’t necessarily reduce this aspect of the scenario as meaning that this family symbolizes a manicheistic world: instead, it can be more beneficial for the spectator to see it as a tool of simplification, without which many of the elements of the family’s system could become too complex to analyze whilst watching the film. What matters most is not so much the “good vs. bad” aspect of actions and words, but rather the very existence of good and bad in the subjects’ conscience, as a filter through which any thought or whim must pass before being embodied into action or expressed. For when it comes to the climax of the story, one of the daughters (Angeliki Papoulia) will not make a choice between good and bad: rather, she will have to choose between obedience to her inner drive or to the system.
If the tooth of a dog is a symbol of threat to the eyes of human conscience, the fall of a “dogtooth” of a human can be seen as a symbol of threat to collective human conscience.
French trailer of "Dogtooth" (watch it on youtube)