With dialogue so rewarding of careful attention, and a plot spring-loaded to keep your mind on its mechanisms, a director who wants to address the bigger implications of “American Buffalo” is left to work at the margins. Pepe, a longtime Mamet colleague, does so mostly by moving the characters like mice in a maze on Scott Pask’s ingenious junk shop set. Filled to the janky rafters with a half-century of capitalism’s castoffs, it suggests the ruined brain of an addled man or the ruined conscience of a country.

It is through that junk — behind tables of tchotchkes and items hanging in our sightline — that we see the action, and also see other members of the audience, as if to say we are all in this business together. What Pepe has the actors do incidentally as they maneuver its cramped aisles is also telling: Don cleaning up, Bobby trailing him like a puppy, Teach idly handling the merchandise. And yet, perhaps, not so idly. The items he chooses to twiddle include dumbbells and boxing gloves and “a thing that they stick in dead pigs” to keep their legs apart as “all the blood runs out.”

Mamet contrasts Teach’s macho postures with Don’s gentler but by no means refined version of masculinity: avuncular yet menacing, slower to anger yet never quite nice. In Fishburne’s big, unshowy performance, you feel the pleasure and pressure behind Don’s creation of that double image. He’s a man of principle who thinks nothing of stealing the valuable nickel for which the play is named; he’s a family man without a family. His tough-love approach to Bobby, a recovering heroin addict who never fails to fail, is touching until you see it for what it is: indoctrination.

Or shall we call it grooming? But that would be to indulge in the same kind of baseless speculation Mamet did about teachers on Fox. In any case, the play draws its big energy and explosive humor from such contradictions. Teach, who carries a gun, is a wuss about the rain. Bobby, a bit of a blank even in the best performances, with lines that rarely stretch past five words, is eager to learn the ropes of a world that has long since hung him out to dry.

I know how Bobby feels. As a lover of Mamet’s early work — “Sexual Perversity in Chicago,” “The Woods” and “Glengarry Glen Ross,” to name a few — I am by now used to the feeling of being cheated by what came later. More recent plays like “China Doll” and “The Penitent” are not just weird one-percenter whines but dull, dull, dull.

This crackling revival of “American Buffalo” highlights by contrast the devolution of Mamet’s craft that coincided with the shift in his worldview, from red-diaper baby to apologist for billionaires. How could the man who showed us how the powerless are crushed by the lessons of the powerful now argue, both in plays and on television, that the problem flows in the other direction?

Not that I wield the ax of cancel culture. As both Teach and Mamet might argue, let the market have its say. (I doubt you will ever see a Broadway revival of the repellent “China Doll.”) But when a playwright begins to sound in life like his characters do onstage, you have to wonder: Who’s teaching whom?

American Buffalo
Through July 10 at Circle in the Square, Manhattan; americanbuffalonyc.com. Running time: 1 hour 40 minutes.