The entire play is set in Orgon and Elmire's home.
At opening, Madame Pernelle, Orgon's mother, is preparing to flamboyantly leave the house. She calls for her servant, Flipote, insisting they must leave immediately. When her daughter-in-law Elmire asks why she is so insistent, Madame Pernelle attacks the family for being immoral, and interrupts all three of the younger people - her grandson Damis, her granddaughter Mariane, and Mariane's servant Dorine - when they try to argue.
Madame Pernelle insists that Elmire dresses herself too finely, and that she has corrupted her children. Cleante, Elmire's brother, also tries to speak, but is interrupted. When Damis mentions Tartuffe, Madame Pernelle sniffs that they ought to pay more attention to him. Damis argues that Tartuffe is only a "trickster" who has banned all fun from the house, and fooled his father Orgon into compliance with his wishes. His grandmother counters that the virtuous Tartuffe is merely modeling for them the path to heaven, while they stupidly accuse him of hypocrisy.
Dorine tries to argue, suggesting that both Tartuffe and his servant Laurent are cads. Madame Pernelle counters that she does not know Laurent, and then claims that neighbors have begun to gossip about the noise and chatter created by the house's many visitors. Cleante suggests that it is natural for neighbors to gossip, and Dorine blames one particular neighbor, a bitter old spinster who judges others to assuage the pain of her faded beauty, for the brunt of the gossip.
Madame Pernelle rebukes Elmire over her uppity servant, and comments that her son Orgon "has done more than wise / In welcoming this man [Tartuffe] who's so devout." After admonishing the family once more, she and Flipote exit the house.
While Elmire and the children see Madame Pernelle to the door, Cleante and Dorine continue speaking on stage. Dorine laments how Orgon, once sane and measured, has become intoxicated by the charlatan Tartuffe, whom he praises unceasingly and beyond understanding. It is doubly disconcerting to see Orgon so deceived because he recently earned public accommodation for supporting the King in a recent war. She believes that Tartuffe is "[playing] him like a guitar!" She also believes that Tartuffe is enchanted by and obsessed with Elmire.
Elmire returns and announces Orgon's approach. Damis worries that his father will no longer let Mariane marry her beloved Valere, as he had promised. Damis knows that Tartuffe opposes the match, and believes Orgon will likely take Tartuffe's advice. He asks Cleante to confront Orgon on Mariane's behalf.
Orgon energetically enters the room, and asks Dorine after everyone's health. When the servant explains that Elmire was suffering a terrible headache, Orgon merely asks, "And Tartuffe?" Dorine continues to catalogue Elmire's suffering, but in a comic blindness, Orgon continues to inquire after Tartuffe, lamenting the latter man's minor troubles.
All but Cleante and Orgon exit, and the former confronts the latter about Tartuffe's influence in the house. Cleante insists that men like Tartuffe are "not so rare" in their outward shows of virtue as disguise for ulterior motives. Orgon explains how Tartuffe inspires him towards love for all, and tells how he met Tartuffe: Tartuffe entered church one day, unknown by everyone, and began to berate himself at the altar for his sins and poverty. When Orgon tried to give money to Tartuffe and his servant Laurent, they accepted only half the money, and gave the rest to the poor. Orgon then heard an inner voice from Heaven, demanding he bring Tartuffe home. There, Tartuffe proved both inspirational and useful, since he watched Elmire as guard against undue advances from other men.
Cleante tries to counter this interpretation of Tartuffe, but Orgon accuses him of being an atheist and a dangerous free-thinker. Cleante tells his brother-in-law that he has been misled by a man who is not a true believer, and has confused "hypocrisy with deep devotion." He suggests that men of true piety do not attempt to illustrate it outwardly, while only the charlatans and phonies insist on flaunting their 'goodness.' When Orgon grows tired of the attacks and takes his leave, Cleante then presses his brother-in-law on the question of Mariane's impending marriage. Orgon dodges the questions, and gives no sufficient answer.
The play opens with a household in disarray, and the central themes of morality and religion are immediately apparent. The play's initial conflict is based around Madame Pernelle's insistence that her son's household is insufficiently pious. It is worth noting that for Moliere's society, religion and morality were not considered separate virtues, but rather dependent ones.
Very quickly, the initial conflict centers around Tartuffe, who is already established as a central character even though he does not enter until Act III. It is obviously improper to allow an elderly family member to leave the home unsatisfied, but everyone is flabbergasted about how to answer her charges, precisely because they do not understand the obsession with Tartuffe. Part of the older woman's problem is that she takes Tartuffe at face value - because he expresses piety, he is a model of piety. Because her family does not express such piety, and dares to challenge Tartuffe's expressions of it, they are impious. The irony for the audience lies in our awareness that she is turning from her family in the name of religion, while they are desperately trying to placate her. By the time she exits at the end of Scene I, the import of the play's subtitle - "The Hypocrite" - is extremely clear, and the conflict between appearance and reality is well-established.
Interestingly, Dorine is established as the arguably strongest character even in this first scene. Though she is a servant, she is the only one who is able to speak in full sentences to Madame Pernelle. All the others are interrupted before they can express an entire thought. She delivers the first attacks on Tartuffe that the family hears - she calls him a "hypocrite" guilty of engineering a "ruse" (5).
When Orgon enters the scene, the potency of Tartuffe's spell becomes immediately apparent. The exchange between him and Dorine is hilarious in performance, as he continues to ask the same question about Tartuffe and them laments the man's minor sufferings with the same exclamation. Further, the way Orgon speaks of meeting Tartuffe reveals the level of his infatuation. It is almost as though he has been seduced by the man's piety, and it is easy to imagine an actor growing starry-eyed in these long speeches of admiration.
The same irony is apparent here as was apparent with Madame Pernelle - Tartuffe has supplanted both family and God Himself for Orgon. In other words, Tartuffe has taken the place of a false idol. However, because Orgon has the delusion of religion to justify his blindness, he is able to chastise anyone who challenges his perceptions. The accusation he lays against Cleante of atheism is no small charge in Moliere's day, and yet it is leveled against someone who is obviously more invested in Orgon's family's wellbeing than Orgon himself is. Moliere levels a not-so-subtle attack on religion by making it the weapon with which Tartuffe blinds Orgon, and with which Orgon deludes himself when faced with the abundantly obvious truth.
Cleante's description of men like Tartuffe makes the play's central themes clear. He describes Tartuffe as a con man, who flaunts himself to engender a picture of true spirituality. A man of false spirituality, he argues, is happy to murder in the name of the Lord, and then defend himself with his piety. The separation between what a man actually is and how he appears is central to Cleante's argument. The problem, of course, is that those whom Cleante describes as actually pious make no outward show of it, and hence never reap the rewards reaped by con men, who usually feign a love of povery but somehow "end up sitting pretty at the court."
This play was controversial in its day (and still is to some religious leaders) because of these attacks on religion. Of course, Moliere is less interested in attacking religion than in attacking how it can be used to support hypocrisy. Both the malicious man and the duped man misuse religion, the former to disguise his intentions, and the latter to ignore the truth that could help both him and his family.
Indeed, both Cleante and Damis are interesting characters in the way they personify arguments against such a human capacity for hypocrisy. While some critics have found Cleante to be a boor or a busybody, others believe him to represent Moliere's voice, since he is a paragon of rationality and reason. His wit and rhetorical skills are pronounced, and his opinion of Orgon seems most likely to represent how the playwright feels. If we accept this interpretation, then it is interesting that Cleante's arguments fall on deaf ears. Moliere might have been presenting his own argument, and then comically acknowledging the futility of such arguments against a world blinded by religious delusion and desire for self-aggrandizement.
Damis works a foil for Orgon and Tartuffe. He is a vociferous ally of the truth, although his brashness and youthfulness lead him to make unproductive decisions. He personifies folly where Cleante personifies wisdom, yet they are allies in trying to dislodge the hypocrite Tartuffe. Damis is equally ineffective in his attempts, but remains a valuable comedic figure. As critic Pamela S. Saur points out, "since we expect caricature, distortion, and excess in a comedy, it is worth considering whether Cleante represents an excess of rationality and mental orientation and Damis an excess of irrationality and emotional/physical (violent) orientation." In other words, they are perhaps meant to represent intentional extremities, different facets of the human personality.
Finally, it is worth noting the way that Moliere's comedy works. The first is in his use of broad characters and behaviors. Though his plays are sometimes criticized for simplistic expressions of individual psychology, the playwright was not interested in fashioning rounded and realistic characters. Instead, they speak and behave in large actions and speeches, so that the audience can laugh at man's unambiguous folly. Orgon's speeches of love for Moliere are quite funny when performed with appropriate exaggeration, but would be less so if they were nuanced with a more grounded, more realistic structure. Further, Dorine fits the comic style by being such an aggressive character despite her low station. She has the agency and language to poke holes in all the delusions that others create, and her scenes with others tend to be the funniest because she functions as the most effective straight man.