Much to the horror of his friends and companions, Alceste rejects la politesse, the social conventions of the seventeenth-century French salon. His refusal to "make nice" makes him tremendously unpopular and he laments his isolation in a world he sees as superficial and base, saying early in Act I, "... Mankind has grown so base, / I mean to break with the whole human race".
Despite his convictions, however, Alceste cannot help but love the flighty and vivacious Célimène, a consummate flirt whose wit and frivolity epitomize the courtly manners that Alceste despises. Though he constantly reprimands her, Célimène refuses to change, charging Alceste with being unfit for society.
Despite his sour reputation as "the misanthrope", Alceste does have women pining for him, particularly the moralistic Arsinoé and the honest Eliante. Though he acknowledges their superior virtues, his heart still lies with Célimène. His deep feelings for her primarily serve to counter his negative expressions about mankind, since the fact that he has such feelings includes him amongst those he so fiercely criticizes.
When Alceste insults a sonnet written by the powerful noble, Oronte, he is called to stand trial. Refusing to dole out false compliments, he is charged and humiliated, and resolves on self-imposed exile.
His friends forsake him, and upon meeting them, he discovers that Célimène has been leading him on. She has written identical love letters to numerous suitors and broken her vow to favor him above all others. He gives her an ultimatum: he will forgive her and marry her if she runs away with him to exile. Célimène refuses, believing herself too young and beautiful to leave society and all her suitors behind. Philinte, for his part, becomes betrothed to Eliante. Alceste then decides to exile himself from society, and the play ends with Philinte and Eliante running off to convince him to return.