If you haven’t spent a lot of time in New York or Southern California, chances are your view of JoBeth Williams is limited to what you’ve seen in movies (Poltergeist, The Big Chill) or on TV (“Frasier,” “Baby M”).

Williams is actually a veteran stage actor. The Houston, Texas native (and daughter of an opera singer), got started the usual way: in high school musicals. In college, she shied away from the theater because her high school counselors had said something to the effect of : “Oh, that’s lovely, dear, you want to be an actress. But what do you want to do in real life?” So, at Brown University, Williams aimed toward a psychology major.

The lure of the drama department, however, was strong. Shortly into her college career, she got sucked into a theater audition and that was that.

She became a member of Trinity Repertory Company, eventually moved to New York and just kept acting.

Movies eventually called – remember her fantastically awkward hallway nude scene in Kramer vs. Kramer, her film debut? – but she never fully gave up theater.

“I never though of theater as a stepping stone to movies or TV,” Williams says. “I have always said I wanted to keep doing theater because it’s what I love most.”

And so she has. Last year, Williams appeared at the Geffen Playhouse in Los Angeles in a new play written and directed by Jane Anderson, The Quality of Life, set in the remains of a burned Oakland hills home. Her co-stars included Laurie Metcalf (of Chicago’s Steppenwolf Theatre and TV’s “Roseanne”), Scott Bakula (“Quantum Leap”) and Dennis Boutsikaris.

That play, and most of that cast, has moved north to San Francisco’s American Conservatory Theater. Metcalf (below right with Williams, photo courtesy of Geffen Playhouse and Michael Lamont) and Boutsikaris play an East Bay couple dealing with major illness as well as the loss of their home. Williams and Stephen Culp, replacing Bakula, play Bill and Dinah, Midwestern relatives dealing with their own loss who come out West for a fraught family reunion.

Williams has appeared in San Francisco before – in the long-running The Vagina Monologues at the Alcazar Theatre, but this is her first major Bay Area drama.

Williams recalls the first time she read Anderson’s script that she immediately wanted to do it.

“I really empathized with my character and the loss she’s been through,” Williams says. “Maybe it’s because I’m from Texas and have cousins who are not born again but good Christian people, salt of the earth people. Her sense of hope and hopefulness moves me tremendously. Reading the play, there were times I didn’t know if I was supposed to laugh or cry, so I did both.”

The rehearsal process, according to Williams, was painful.

“Because of the nature of the material, dealing on a daily basis with that kind of loss…it felt like someone had beaten me up by the end of the day,” Williams says. “At the same time it was exhilarating to get to practice your craft and go into deep places. When you can do it, when you’re well used, it’s cathartic. It was difficult but incredibly rewarding.”

If the ACT run goes well, Williams hints that The Quality of Life could be heading for New York.

Assessing her stage career up to this point, Williams calls her stint as Cleopatra in the Old Globe’s Antony and Cleopatra one of her favorites. She’s also fond of Body Awareness, a play she did earlier this year at New York’s Atlantic Theater Company.

“The play is by this young writer, Annie Baker, and I play a high school teacher in Vermont who has a son with Asperger syndrome and a girlfriend who’s a college professor,” Williams explains. “This straight man, a visiting artist, comes to stay with us and it’s just a very funny play about jealousy and relationships and the difficulty of dealing with people. It’s something I think should be seen in San Francisco.”

Based in Los Angeles with her husband, TV and film director John Pasquin, the 59-year-old Williams still works regularly in film and on TV.

One of her favorite roles came in the 1991 big-screen comedy Switch with Ellen Barkin.

“I got to play this rich bitch, a really mean sort of snotty woman who kills a man,” Williams says with glee. “It’ was so much fun to play that part. I’m mostly cast as a sweet, nice mommy, but that’s really not who I am. I’m really a raving bitch. It was nice to play something closer to home. That’s what’s fun.”

When Williams was doing The Quality of Life in Los Angeles, she was impressed by the devotion of co-star Bakula’s fans – called Leapers after his old sci-fi TV series – who would come to the play night after night and bring the actor flowers and fruit and such.

There would be people at the stage door with Poltergeist posters and such for Williams to sign as well, but her fans weren’t so organized. Perhaps they’ll get organized in the Bay Area. But what would such a group be called?

Williams ponders the question for a moment. “I don’t know, maybe Poltergeisters…or Big Chillis?”

The Quality of Life begins previews today (Friday, Oct. 24), opens Wednesday, Oct. 29 and continues through Nov. 23 at American Conservatory Theater, 415 Geary St., San Francisco. Tickets are $14-$57 for previews and $17-$82 for regular performances. Call 415-749-2228 or visit www.act-sf.org for information.

On a personal note, I happen to think Williams’ performance as a traumatized mother in Poltergeist ranks as one of THE great mother-in-distress performances on film. The fact that the performance is in a hit horror film means – for whatever reason – that Williams’ superb work has been criminally underrated. Watch the movie again – Williams isn’t in a horror movie. She’s in the most intense family drama imaginable. She’s extraordinary, and she grounds a nearly ungroundable film.

On the lighter side, follow this link to hear the charming Williams talk about her Kramer vs. Kramer nude scene:

http://link.brightcove.com/services/link/bcpid192878566/bclid1163333263/bctid1114968511