"Macbeth" without a riveting Macbeth may not be the best of affairs. But the shortcoming is not as disastrous as you might expect. Consider the production of Shakespeare's shortest, swiftest tragedy, which opened Monday night at the Shakespeare Theatre at the Folger.

Philip Goodwin, a perfectly serviceable if hardly inspired actor, is playing the bloodthirsty Scotsman. The performance is intelligent, clear and not without its moments of passion. But Goodwin doesn't go the distance. Something's lacking -- an amplitude, an abandon, the uncontained monstrousness of a man bloated by evil.

Is the actor's slight physical stature to blame? Or the voice, which, when it takes on volume, tends to sound strangulated? Just when we want Macbeth's emotions to swell and break over the play like a dark wave, Goodwin turns in on himself and knots up. This Macbeth has less in common with the raging tyrant, slaking his ambition at any cost, than he does with the petty bureaucrat who, denied a raise, fulminates secretly against his bosses in the mailroom.

And yet, in a curious way, Macbeth's weakness prompts us to refocus our attention elsewhere. And elsewhere, this is as bold and vibrant a staging as any the Shakespeare Theater at the Folger has given us since last season's "Romeo and Juliet." You may not come away with fresh insights into the title character, but you will be struck -- stunned even -- by the poisonous world he inhabits.

Director Michael Kahn, indulging the Jacobean side of his nature, has orchestrated a fiercely claustrophobic production, in which the air itself seems to have been replaced by fetid smoke and blood runs as freely as water. British director Peter Brook once staged "A Midsummer Night's Dream" in a white box. Kahn has encased his "Macbeth" in metal.

At the start, two huge portals, battered by the elements, shield us from the brewing poisons. When they open, it is not to reveal expansive vistas, but shrunken rooms and hidden crannies. There is no breathing space here. Shakespeare's characters have been thrown up against one another, as if in a madhouse or a nightmare.

Indeed, the three weird sisters, who prophesy Macbeth's cursed destiny, are no longer to be found on the windswept heath. Kahn introduces them into the bosom of the court, where they dutifully pay attendance to Macbeth and his wife and even dare take communion -- their tiny hands folded in seeming piety, their all-knowing eyes downcast in an imitation of servility.

Sometimes, the doors, partially closed, let shafts of light escape, suggesting the existence of endless dank corridors. In one vivid battle scene, they swing on their hinges, sweeping before them the combatants as if they were so many balls of dust. The gates of Hell may look like this. By the end, Michael Yeargan's set certainly seems to possess a mocking malevolence all its own.

No majesty graces this universe -- just perversion feeding on itself. When Lady Macbeth (Franchelle Stewart Dorn) rouses herself from her bed for her feverish sleepwalk, she will only make it halfway down the castle staircase. Draped over the steps, like spilled blood, is a bolt of red cloth. In her folly, she gathers up the fabric in a bundle, and then cradles it lovingly in her arms. It's an arresting -- and thoroughly apt -- expression of the blighted maternal instincts souring her soul.

As Dorn plays her, which is vigorously, Lady Macbeth is the nurturing force run amok. She thoroughly dominates Macbeth, ridicules him with scorn, tantalizes him with her sexuality and generally goads him well beyond his limits. Macbeth is not so much her husband as her plaything. With hair that cascades almost to the floor and a grave voice that can turn scaldingly shrill, the actress seems animated by a primitive Attic passion.

Goodness pales by comparison. It is not the fault of Phebe Finn (Lady Macduff), Edward Gero (Macduff) or Robert Jason (Banquo) that their decency registers with considerably less force. The performances are sober and disciplined, with a natural uprightness that eschews heroics. On the stage, if not in life, however, evil is intrinsically more interesting than virtue, which tends to appear bland by comparison.

Theatrically speaking, nothing becomes this Lady Macduff so much as the violent slaughter that Kahn has reserved for her in a courtyard hung with laundry. Banquo's gray ghost, materializing behind a silvery mirror in the banquet hall, piques our attention in a way the living man never does. Gero may struggle manfully with the loss of wife and children, but Macduff's moment of stage glory doesn't really come until he eviscerates Macbeth and the battered carcass is hoisted high above the stage on thick ropes.

One can imagine, I suppose, a "Macbeth" that forgoes all the gore and violence to concentrate exclusively on the psychology of the evil personality. That is not, however, what Kahn seems to have had in mind. His production doesn't dissect a disease; it lays out the inexorable ravages, often with a headiness that dares to be gainsaid.

Stronger than any of the characters, willful as they may be, is the sense that the universe is fundamentally askew. Macbeth and his Lady Foul have not turned their back on the light. There is no light to begin with -- only flickering torches that momentarily dispel the cryptlike blackness. And when the action moves out of suffocating chambers into the great outdoors, it is bathed in more viscousness. The sun, if it hasn't burned itself out, emits only a cold, flat whiteness.

Stephen Strawbridge is the gifted lighting designer. But what he has really designed is a horrible void that will be slowly and inexorably filled with putrefaction. This "Macbeth" could well be taking place shortly after Pandora lifted the lid on that fateful locker. No one, least of all Macbeth himself, stands a chance against the contagion.

Macbeth, by William Shakespeare. Directed by Michael Kahn. Set, Michael Yeargan; costumes, Smaranda Branescu; lighting, Stephen Strawbridge; composer, Robert Parris. With Philip Goodwin, Franchelle Stewart Dorn, Robert Jason, Geoffrey Lower, Edward Gero, Phebe Finn, Emery Battis, Rosemary Knower, Catherine Flye, Leah Maddrie. At the Shakespeare Theatre at the Folger through April 10.