Tanya Shepke is your white-trash everywoman. Locked up for drunkenness in her hometown of tiny Lodus, Missouri, she pours forth a nonstop torrent of profanities, abuse, innuendo, and half-baked excuses for her bad behavior.

She’s an unlikely heroine—yet that’s her role in Jason Wells’s The North Plan, an odd blend of dark political satire and murder-‘n’-mayhem farce, directed by Kimberly Senior, that just opened at Theater Wit.

And that’s what Chicago favorite Kate Buddeke makes Tanya: a heroine. I think. This veteran not only of Chicago stages but of Broadway, TV and film somehow hints at the tiny kernel of moral responsibility that might or might not be at Tanya’s core.

Asked whether she resembles Tanya, Buddeke says, “Let’s hope not. I don’t swear as much. And I like to think that I think a little more than Tanya. She’s a real motor mouth.”

“But, with every character, I think there’s a bit of me in it. With this one, it’s her balls!” (At the final preview, the audience broke into cheers after one of Tanya’s triumphant exits.)

Wells’s 90-minute two-act, which debuted here in 2010 as part of Steppenwolf’s First Look series, breaks in half at the intermission—which seems to exist mostly to allow an elaborate switch of Jack Magaw’s ingenious set. The relatively serious first act sets up a culture-wars situation and the political context: federal bureaucrat/Jewish liberal Carlton, in the pen next to Tanya’s, has been jailed under a repressive, lawless new regime.

But Buddeke says she doesn’t think of Tanya—the seeming representative of poor white southern females everywhere—in terms of politics. “She’s so non-political. Truly, as I’m in this play, I have no idea what’s gonna happen, certainly not on a political level.”

That’s partly because all hell breaks loose in the second act, which takes a hairpin turn into farcical violence. “It gets really comic and crazy,” says Buddeke.

“I’m not known for comedy,” she adds. “And that was intimidating at first. It’s black comedy, of course, and the comedy I usually do is more realistic, not so out there. I was a little scared of it.”

“But it’s freeing. The first 15 to 20 minutes go by so f**king fast, you don’t have time to worry about anything—just do it!” Tanya’s opening tidal wave of words is so repetitive too that “there’s always a moment where I think, ‘Where am I?’” says Buddeke.

Comedy aside, Tanya does make a distinct shift between the first and second acts. “Part of that is that it’s her choice to walk into that room,” says Buddeke. “She’s making choices—it’s a different situation: ‘I’m not leaving.’”

Believe me, the room wouldn’t be the same without her.