The cast of "August: Osage County" (featuring Deborah Hazlett as Barbara attacking her mother, Violet, played by Linda Thorson) at Everyman Theatre. (Stan Barouh/Stan Barouh)

Can you really dare to open a new theater these days with a 31 / 2-hour marathon? Can you risk producing a play — not a musical — that requires 13 actors? Can you bet all your chips on something as quaint, and something so nearly extinct in the American theater, as an acting company?

Vincent Lancisi says “Yes!” — and the explosively funny production of Tracy Letts’s “August: Osage County” at Baltimore’s Everyman Theatre is backing him up. The large cast artfully slugs its way through the shock and muck of lies, booze, pills and toxic hookups in Letts’s chronicle of an Oklahoma clan’s spectacular flameout. It’s an exuberant, aggressive opening: You can’t accuse Everyman, founded by Lancisi in 1990, of tiptoeing into its attractive, new $18 million theater near the Inner Harbor.

The building is a spacious 1911 vaudeville house that Everyman has converted into a 250-seat theater intimate enough for actors to connect easily with audiences, yet wide and tall enough for a large-scale play like “August” to resonate. Everyman’s previous home on Charles Street was hobbled by an 11-foot ceiling, so the three-story house that set designer Daniel Ettinger creates for “Aug­ust” must feel like a skyscraper to director Lancisi and company.

That “company” is inescapable, from the faces of Baltimore-based actors proudly displayed on the banners outside on Fayette Street to the blown-up wall photos and wall-sconce ghost figures inside. And although “August” is a group effort, it is one of Everyman’s own, Deborah Hazlett, who especially powers the long-distance drama to what feels like a sprinting finish.

The deceptively straightforward Hazlett plays Barbara, the eldest of three grown daughters who have gathered at the family home in the wake of their father’s mysterious disappearance. (Carl Schurr sets an intelligent, enigmatic tone in the father’s lone early scene.) Hazlett is near effortless with Barbara’s tragi-comic complexities as she squares off against her monstrous mother, Violet, and wrangles for family control in ways that grow darker and more scandalously funny with each secret that gets dragged into the light.

An exterior shot of the new Everyman Theatre. (Stan Barouh/Stan Barouh)

Violet, the aging matriarch, is vicious, thanks to mouth cancer and a habit of depressants by the fistful. Linda Thorson — Diana Rigg’s successor on “The Avengers” TV series, making her Everyman debut — is like a serrated blade as Violet, lean and wobbly as she jabs physically and verbally at her hapless relations. The wide family circle includes Violet’s air-headed middle daughter, Karen (a blissfully self-absorbed Maia DeSanti); her youngest daughter, Ivy (Beth Hylton, mousy); Karen’s predatory fiance, Steve (Bruce Randolph Nelson as an aging funboy); Barbara’s philandering husband, Bill (a defensive Rob Leo Roy); and many more. It’s a play with no cheap roles, and Lancisi’s cast shows no real weak spots.

In particular, you feel like you could listen to Hazlett’s Barbara and Roy’s Bill spar all night, and the prickly exchanges between Violet’s on-edge sister (acclaimed D.C. actress Nancy Robinette) and her understated husband (Baltimore stalwart Wil Love) have a rewarding frisson. No doubt the troupe is still learning the new stage, but the cast has come out of the gate with assurance.

Lancisi’s formula is simple: mainstream plays plus the best actors (largely local and familiar) he can grab. The season’s upcoming “God of Carnage,” “Topdog/Underdog” and the classic “The Beaux’ Stratagem” break no new ground, except, as Lancisi likes to point out, each work is a Baltimore premiere. Everyman is only the city’s second fully professional resident theater after Center Stage (in business since 1963), so the meat-and-potatoes approach seems right. Let the actors have at it.

August: Osage County

by Tracy Letts. Directed by Vincent Lancisi. Lights, Jay Herzog; costumes, David Burdick; sound design, Chas Marsh. With Clinton Brandhagen, Veronica del Cerro, Ron Heneghan and Heather Peacock. Through Feb. 17 at Everyman Theatre, 315 W. Fayette St., Baltimore. 410-752-2208.