Blanche DuBois turned 50 last year. It’s tempting to think how she might look so many years later and what happened to her and what kind of kindnesses she’s been depending on from strangers these days. But it’s more fascinating to look at how she has — without aging a day — matured into one of the most compelling dramatic characters of this century.

“Blanche DuBois, c’est moi,” said Tennessee Williams, whose 1947 play “A Streetcar Named Desire” changed American theater forever and also immediately won both the Drama Critics’ Circle Award and the Pulitzer Prize. A new production of “Streetcar” lustily opened last week at The Opera House under the direction of Penobscot Theatre’s Lisa A. Tromovitch, who shows in some deeply American way that Blanche DuBois, c’est toi, too.

An adaptation of an earlier play called “The Poker Game,” “Streetcar” originally focused on Stanley Kowalski, another resounding American character. Williams changed the name of the play to reflect New Orleans and shifted his attention to Blanche. In doing so, he opened the wounds of American history. Not only is Blanche the outmoded Southern belle, she is the fading woman whose charm has withered along with her youthful beauty.

Blanche wants magic rather than reality. She wants a colored paper lantern rather than a naked lightbulb that starkly shows the wrinkles. She pretends to be virginal, genteel and happy, when she is quite the opposite. And Maura O’Brien, a newcomer to Penobscot Theatre, gives Blanche all the fantasy a woman could possibly fit into her wardrobe trunk and jilted heart.

O’Brien’s performance begins at a high and breathless pitch and, initially, it seems as if she depletes herself early on. It doesn’t help either that she arrives looking more like Miss Havisham rather than a has-been beauty. O’Brien doesn’t have the edge Blanche should have, and she sometimes slips into a cartoonish madness. But with the progression of scenes, O’Brien unravels a woman who is complex and wily. Her performance is finally dimensional enough that we pity Blanche at the end of three hours.

Derek Stearns, last seen as Mozart in Penobscot Theatre’s production of “Amadeus,” is a clipped and fierce Stanley Kowalski, whose animalistic sensibilities bulge from beneath his muscle T-shirt and roar from his drunken poker games. As with O’Brien, Stearns has a gift for humor. Whether there’s such a strong call for the sitcom style in this play is another question. Fortunately, Stearns can be frightening, too. Opening night, he brought the house down with one of Stanley’s lines that has contemporary salience. The moment has nothing to do with Williams’ play, but it gets a deserving laugh.

Stearns and Deborah Elz Hammond, as Stella, work in consort to create the image of a couple stuck in some pretty shameful codependent happiness. Hammond’s performance is sexy and smart, and somehow persuades us to be sympathetic with her horrible, inevitable choices. And what a set of lungs Hammond has on her, too. Her final screams are haunting and raw.

Davidson Kane, as Mitch, is both gentle and crude, which is the right combination. Supporting roles by Bob Field, Joseph McGuire, Cathy Plourde, Ricardo Rosado and David Sperry keep the show moving. Chuck Cronin puts in a kindly appearance in the final scene, as does Catherine LeClair, as an awkwardly cruel and spooky nurse who steps out of some other morbid script altogether.

Jay Skriletz’s transparent walls let us see into the unhinged lives of these characters, and Lynne Chase’s symbolic lighting notches up the stylized look of the show. Costumes by Odelle Bowman range from womanly to redneck.

Parts of the show are unevenly structured, and Williams’ poetry is too often tossed aside for a more 1990s terseness or an elongated moment of drama. On the other hand, there are some steamy scenes that truly work. The actors still are not vocally managing the larger performing space, and it’s an all-out shame to miss even one word of Williams’ astounding script.

A final note: The Kowalskis may live in New Orleans, but artistic director Mark Torres is paying the heating bills here in Maine. Wear your down parka and wool socks. The theater is cold.

“A Streetcar Named Desire” will be performed 7 p.m. Thursday, 8 p.m. Friday, 5 and 8:30 p.m Saturday and 2 p.m. Sunday through Feb. 22 at The Opera House. For tickets, call 942-3333.