If ever a play called out for a bravura performance -- one that it is not getting, alas -- it is David Pownall's "Master Class."

This British drama, which opened Sunday night in the Kennedy Center's Eisenhower Theater, may not be the profoundest work to cross the ocean, but it bursts with possibilities for high-voltage tension and runaway theatrics. If you're going to detonate its obvious power, however, you need a Stalin. Or at least an actor who can go from the heights of arrogance to the depths of self-pity, who can be as wily as a fox and as self-satisfied as a bullfrog, who can scare and charm and cajole the collective pants off an audience.

You see, Pownall's play, which is set in a particularly grim hall in the Kremlin in 1948, imagines what might happen if Stalin himself took it into his head to instruct Prokofiev and Shostakovich in the duties of the composer and the nature of "the definitive new Soviet music." The premise is fictional, although the Soviet propensity for revisionism certainly makes it credible enough.

Adding insult to ignorance, "tone-deaf Joe from Georgia," as his trusty military sidekick calls him, refuses simply to chastise and lecture the celebrated composers. He decides to pool his musical expertise with theirs: together they will sit down at the piano and write a folk cantata that will go straight to the heart of the masses. It will be on an idiotic theme of Stalin's own choosing, of course, and in the key of his liking. (That key is not easily settled upon, since he seems to regard B-flat major, for example, as if it were a recalcitrant army officer to be dismissed with a disparaging wave of the hand.)

No matter. When you're the number one piper of the Soviet Union, you call the tune. You also call the words. Among those Stalin wants incorporated into his cantata is this bewildering observation: "To him who has been struck in the liver by a snake, treacle is better suited than red candy." Who wouldn't blanch under such a commission?

If Stalin knows next to nothing about music, he clearly knows everything about intimidation and Pownall sets him on a maniacal rampage that is not without its grotesque merriment. What we have here is the age-old bully of the class -- the socialist class -- taking after the eggheads and making them squirm. The danger and discomfiture that ensue make for a potentially unique tone: one that could have you recoiling, even as you are laughing on the edge of your seat.

I am sure you sense the trap, though. No other character is going to lift a finger, express an opinion, or even stir from a position of terrified subservience, until commanded. Shostakovich and Prokofiev, in fact, would just as soon melt into the glum, gray walls. Stalin's sidekick, Marshall Zhdanov, allows himself occasional outbursts of vituperation -- only because he's trying to emulate his hero's shining example. Stalin calls all these dramatic shots.

But in the Center's production he isn't half the tyrant he could be. Although the role is played by George Dzundza with some competence and an intelligent understanding of the tumult raging in Stalin's breast, it's a youthful performance, still couched in layers of baby fat. Dramatically, Dzundza climbs hills and descends into valleys when the play cries out for him to scale mountains and plunge into ravines. You keep wanting him to do more.

Pownall's play has some startling moments to spring on an audience. At the end of the first act, Stalin and Zhdanov methodically comb through a box of records, presumably in quest of Prokofiev's finest composition, and then end up ruthlessly smashing them to the floor, one after another. In the second act, Stalin sinks into the quicksand of his memories of World War II, when a generation marched off to its death under his steely command. And we realize that his fanatical, absurd concern with a music that will heal and uplift his people is rooted in guilt -- maudlin, pernicious, paralyzing guilt.

But this production, directed by David Trainer, doesn't rise to those heights. The supporting players find themselves in that most awkward of positions -- having to define themselves in terms of a central performance that isn't fully there. With his puffy, resigned face, his hesitant step and his beleaguered airs of faded aristocracy, Werner Klemperer gives every indication of being within striking distance of Prokofiev. Michael Zaslow plays Shostakovich as a jumpy bank clerk, so certain he's going to slip up in his addition that he invariably does. If Dick Latessa seems to be wildly overstating Zhdanov, he may not be entirely to blame. Like plasterers, who can't get down to their real work until the scaffolding has gone up, these three are forced to make busy gestures and look engaged, when they're really cooling their heels.

David Jenkins has provided a chillingly appropriate set for them to tremble in -- a huge vaulting room, its massive columns bearing the faint traces of long-ago religious paintings. And opening off this hall is a dank bathroom -- for retching in. The combination of Stalin, yellow vodka and a late night of baiting is lethal, after all.

Except that it's not. Not yet. We won't see the fascinations of Pownall's play until Stalin sharpens his claws and polishes up the mad gleam in his eye. For the time being, this "Master Class" is being conducted without a teacher.

MASTER CLASS. By David Pownall. Directed by David Trainer. Sets, David Jenkins; costumes, David Murin; lighting, Martin Aronstein. With George Dzundza, Werner Klemperer, Dick Latessa, Michael Zaslow. At the Eisenhower Theater through Oct. 20.