The Threepenny Opera is about the values of the bourgeoisie. The criminals in Brecht’s play ape the values and conventions of the middle class. Like prostitution, begging and theft are depicted as businesses. The thief Macheath, a sort of gang chieftain, is in business, bolstered by an army friendship, with the High Sheriff; the business of begging is organized by types of begging and districts by the Peachums; and, overlaid by the sentimentality of melodrama, the society depicted is a recognizable analogue, reinforced by ceremonies and dramatic situations of comedy, to “respectable” middle-class society.

Beyond merely making of this material a pleasant revue using popular music, as John Gay did, to spoof the posturings of the middle class, Brecht has his mock-opera satirize the audience’s values, propagandizing against the decadence of capitalism. Not that his works espoused a particular course of political action—on that suspicion Brecht, a refugee from Nazi Germany to the United States, once found himself called before the House Committee on Un-American Activities. Rather, these productions put the comfortable platitudes of the middle class into the mouths of the villains of melodrama.

The themes—poverty, the exploitation of the poor, the hypocrisy of prostitution, of law enforcement, and indeed of capitalism—reverberate like harsh music through the old plot structure of boy meets girl, parents persecute boy, boy escapes. Brecht uses that formula as a criticism on itself. In scene after scene, as in the wedding reception, the juxtaposition of the criminal context and the middle-class event holds the criminals up for sympathy; the middle class, to ridicule.

Marriage, adolescent rebellion, parental control, middle-class values, friendship, legal ethics, sexual behavior—none of these subjects is the sole theme of this complex drama. Even theater itself is held up for examination as a political statement in support of the power structure.

Betrayal and Moral Corruption
As in the ''greatest story ever told,'' the story of Jesus, the protagonist of The Threepenny Opera is betrayed by a former intimate. But there the similarity ends, or rather, diverts to mirrored opposites. Macheath is not a savior like Christ but a moral corrupter, not a paragon of virtue but a fountainhead of sin, not the archetypal human ideal but a base man of bestial instinct. In contrast to Jesus, he maims the woman with whom he has been sleeping in a stable rather than being born of a chaste woman in a stable. The wedding gown and gifts are not humble attire and ritual offerings but stolen goods.

Despite these oppositions to one of the best-known symbols of purity, Macheath is not a completely evil figure. He has some appeal, especially to the whores and women of low virtue. He is gallant in his way, cuffing his gang members for not displaying enough gentility to his new bride; he has courage, or at least disdain, for his fate; and he has a loyal friendship with his army buddy Jackie Brown. He has a roguish charm but his personality is presented not as a role model but as a warning against the seductive quality of such a dishonest life.

Nor is Macheath the only false idol in the play. Peachum is in the business of guiding beggars to larger profits falsely earned in the name of charity. He preys upon the generosity of the public, justifying his use of false wounds and artificial limbs with his own twist on the biblical homily "Give and it shall be given unto you." Peachum argues that people are jaded and must be prodded to charity by ever-newer and more ghastly representations of poverty. Yet the proprietor takes a whopping fifty percent of his beggars' earnings, betraying the very purpose of begging through his swindling.

Peachum also betrays his own daughter by having her new husband arrested. The whores are the chorus of this play, and they are as corrupt as the main characters. Low-dive Jenny (J as in Judas), a former lover of Macheath's, betrays him for a handful of money, which she is denied when Macheath escapes. In fact, Macheath has escaped due to the betrayal of the jail guard, whom the robber-king has bribed. Furthermore, the whores know Macheath has escaped, and effectively are betraying Peachum when they demand payment for a job that was not satisfactorily completed. The list could go on, including Jackie Brown, who seesaws morally as he wrestles with remaining loyal to Macheath versus saving his own reputation and livelihood. The ubiquity of the corruption and betrayal in The Threepenny Opera goes beyond social criticism to a kind of macabre, black humor.

Art and Experience
The purpose of Brecht's plays (as they were originally staged by the author) was to create an experience that would force audiences out of their common perceptions of bourgeois theater (as merely a means of entertainment). His plays sought to instill a willingness to work for social change. Thus, ultimately, Brecht's plays were designed as tools of moral and social propaganda, yet they strangely lack what most propaganda, by definition, carries with it: a design for a Utopian social paradise that social reform might achieve. Brecht's plays are largely pessimistic: they offer what biographer Martin Esslin chose as the subtitle to his book Brecht, a Choice of Evils, rather than the choice between a right and a wrong way to live.

This aspect of Brecht's work has garnered much critical attention and warrants further contemplation. In The Threepenny Opera, the opera format—already stretching the viewer's sense of realism—is made even more alien through constant reminders of the artifice of the play. Placards announcing the events and songs, asides to the audience, and lyrics incongruent with the action disrupt and sully any positive sentiments being expressed. For example, when Brown and Macheath reminisce about their days in the army, the ditty they sing cynically celebrates the fate of all soldiers to be chopped into tartar (ground meat). When Peachum complains about his lot in life, he sings that God has humankind in a trap that is a ''load of crap." In both cases, what might be profound social commentary is turned into a sick joke. In places, Brecht does address seriously the social ills he wants his audience to face and be moved to change. But he does not offer answers or a rectifying course of action. Rather than offer pat solutions to complex social problems, Brecht forces the spectator to ponder these issues and arrive at their own remedy.