The set-up: Halloween may be over, but its eerie chill lingers through mid-November at Theatre Southwest where a superlative production of Martin McDonagh's dark and dank The Pillowman (2003) elicits icy shivers.

These aren't the jump-out-and-scare-you type of chills, although there are a few frights in the police-state interrogation room where the tale is set, but more subtle psychological thrills. McDonagh conjures these with singular mastery, easy as if he were sitting around a campfire. It's creepy and gothic, the stuff of nightmares. Theatre Southwest's production, also, has its own distinct chills: evocatively simple set (Xandra Homes), brilliant lighting design (John Baker), atmospheric sound (Trevor B. Cone), stunning direction (Scott McWhirter), and immaculately empathetic acting. This is must-see theater on every level.

The execution: Impoverished writer Katurian (Aaron Echegaray), who works in a meat slaughtering plant, lives for writing. Only one out of hundreds of his short stories has ever been published, but they are his very life. He tells stories because storytelling is what he does best. His gruesome fairy tales, most of which involve mutilation, torture, and/or disfigurement of innocent children, are morally ambiguous, socially neutral, apolitical. "I'm not trying to say anything at all," he desperately apologizes to the policemen interrogating him (Scott Holmes and Trevor B. Cone). They don't believe him.

He's been brought to this sterile bunker for questioning. We see him fidget at the table, alone, with a blindfold over his eyes. His image is projected behind him in a high-contrast, almost negative image. Big Brother is watching. The sounds of dripping water and an electric hum unnerve him. These unnerve us, too. Why is he here?

A gruesome series of child murders in this unnamed city in this unnamed totalitarian country exactly parallels his stories. The children have been killed just like his young characters. The case file bulges with his manuscripts, that's the proof. All they want his his confession. Sign it or we'll torture it out of you, they say smugly. Ah, hell, we'll torture you anyway. If he didn't do these grisly crimes, perhaps his beloved "spastic" brother Michael (Sam Martinez), held in the next cell, did. We hear his brother's tortured screams while he's interrogated.

Everyone tells stories in this play. Everyone makes sense of his senseless life the best he can. Katurian's stories evolve from childhood memories under his parents' educational experiments that were either insanely misguided or insanely twisted and sadistic. Either way, stories flowed out of him. Michael has stories, too, awful and searing, but he'd rather listen to Katurian's. The policemen tell stories, but they have their own vaudeville comic routine of good cop/bad cop that interrupts the telling. Everyone's a Scheherazade. None more so than McDonagh, who intrigues us every moment with his bizarre tales and gallery of grotesques.

The Pillowman is not your grandfather's Brothers Grimm or his Marquis de Sade, either, but a shuddering mix of the debauched darkness within us punctuated with unexpected comic flourishes. No contemporary playwright does black humor with the sheen of McDonagh. He polishes depravity until it glistens like onyx. One moment we laugh at the policemen's Mutt and Jeff antics, then gasp immediately after when Katurian is sucker punched. These two gentlemen of the law are a dangerous comedy duo: solicitous, insidious, vicious, kind. They keep us off balance, like poor Katurian.

If you're unaware of the prestigious McDonagh, he burst onto stage with The Beauty Queen of Leenane (1996), a searing Irish mother/daughter slug-fest; followed by the darkly ironic The Cripple of Inishmaan (1996), recently acclaimed on Broadway starring Harry Potter's Daniel Radcliffe; The Lieutenant of Inishmore (2001), a blackest-of-black revenge comedy with daft characters awash with blood; and A Behanding In Spokane (2010), his least successful blood feud.

Maybe you caught his feature movie debut In Bruges (2008), starring Colin Farrell and Brendon Gleeson as inept Irish hit men, an Academy Award nomination for Best Original Screenplay. McDonagh celebrates losers and lowlifes, placing them into impossible, cartoony situations that ramp up the irony along with the gore. Neither civilization nor family receives high marks. Blood and body parts are venerated with as much gusto as McDonagh's forebears, those auteurs at the Grand Guignol. He's theater's Quentin Tarantino. In love with the magic of make-believe, he's a master of structure, and his timing (of jokes, situations, revelations) is impeccable. He knows the exact moment to sew up a thread woven scenes ago, when to fire a gun, or the right time to smother your brother.

No offense against Laura Chapman, Dan Garner, or Holly Harris, as Mother, Father, and Girl, who handle their supporting roles with admirable deftness, but the main players give this drama unimpeachable life and power. The four principals are exceptional.

Echegaray's Katurian reveals hidden recesses inside his character's wounded soul as if shedding veils. Though unsuccessful writer, he knows the power of his pen and how good his stories are. Listen to the variations Echegaray wrings from reciting his stories. No need for theatrical effects, fog, or spooky lighting, when it's all there in his voice, his eyes, his carriage. He sets the mood with alluring immediacy, and there isn't a sound to be heard throughout the house. This is spellbinding storytelling at its finest: the art of acting. Conceited, moody, scared, then battered and bruised after the police treatment, Echegaray's Katurian shatters when Michael confesses. With heartbreaking tenderness, he forgives his damaged brother for such monstrous acts but realizes what he must do to protect him from the police. If Katurian is damned, at least he hopes his tales will survive.

Full of tics, jerks, and childlike wonder, Martinez discovers all sorts of novel ways to paint his character. Petulant like his brother, he has innocent deviltry and a savant's clarity. It's possible he's the killer. At first he says no, but then under Katurian's prodding and intimidation he says yes. Is he? Or is he telling a story his brother wants to hear? Act II's dramatic cell scene, lit as if the brothers were the only two people on earth, is the most sustained piece of theater I've seen this season. With wavelike tension, revelation piles upon revelation until the inevitable, unbearable conclusion. It leaves you breathless.

Holmes and Cone are picture perfect as the police tag team, Topolski and Ariel. They, too, have secrets to tell. Cone is the state's muscle, happy to apply electrodes to Katurian at the least provocation, while Holmes is sly and more cerebral, but just as dangerous, an angry, aloof observer. Ruthless and crafty, these functionaries of the faceless government hold all the cards. That they get so much wrong and then bicker about procedure like Burns and Allen is a wonder to behold. They play off each other like pros.

The verdict: After McDonagh's creepy fables have been told, you leave Theatre Southwest a bit wary of the shadows. Once home, you may want to stay awake a little longer. With a wicked wink, McDonagh shines a harsh light on the human heart, and a good night's sleep is not promised. A comforting small light down the hall wouldn't be out of place.

The Pillowman continues through November 15 at Theatre Southwest, 8944-A Clarkcrest. Purchase tickets online at [email protected] or call 713-661-9505. $15-$17.