Andrew Bujalski writes his films with its nominal stars in mind first, and from there runs with the story. In the three features he's made — the human dramedies "Funny Ha Ha," "Mutual Appreciation" and his latest "Beeswax," made in Austin and opening today at the Alamo South — the filmmaker was lured by the magnetism of certain friends, then fashioned all-too realistic worlds that they could inhabit.

For 2002's "Funny Ha Ha," he drafted Kate Dollenmayer to play a post-collegiate woman insecurely striking out in the world and striking out in love. In 2005's "Mutual Appreciation," Bujalski tapped Boston musician Justin Rice to play a Boston musician very much like himself and nudged the character into the nervous uncertainties of interpersonal connections.

"Beeswax" was sparked by Bujalski's decade-plus friendship with twin sisters Maggie and Tilly Hatcher.

"I find them immensely charismatic," Bujalski says. "Which is the same trick I pulled with Kate and Justin. They were people I knew who had a kind of charm that I thought I could wrangle and get into a shape that would hold the screen and that I could build a story around. None of them are professional actors ... More and more I'm realizing that the kind of charm I respond to so much is not something I see on screen a lot."

He's right. The qualities his actors deliver on screen are rare. Bujalski, who also writes and edits his movies, grants his performers plenty of space in which to shamble their way through, improvise when the moment calls for it and generate a real-time friction that can feel itchily intimate. Dialogue tumbles forth in unstudied clumps and tangles — these are chatty films — producing a loosely shaped naturalism that makes burnished Hollywood fare look shellacked and airless and phony.

"I need a layer of exploration and discovery that non-professionals intuitively bring because, in a way, you're watching people learn the process of acting as they go," Bujalski says.

Casting the Hatcher sisters raised its own challenges, because Tilly is in a wheelchair because of a spinal tumor she's had since childhood. Her condition is never remarked upon in "Beeswax," because her friends and family, as they would be in life, are already familiar with her disability.

Bujalski and Tilly wanted the film to be about her character, not her affliction. "We'd never really seen a disabled movie character treated as a normal person," he says.

"Beeswax" adheres to the ragged, talky indie aesthetic some have dubbed "mumblecore." But, compared with Bujalski's prior movies, the new film is motored by more traditional plot mechanics. Amid the usual Bujalski concerns of negotiating love and relationships on life's shaky ground is the drama of a lawsuit between two business partners (one played by Tilly) who run a vintage clothing boutique in Austin.

"Fear of a lawsuit is driving the story. The movie's so much about anxiety and how in a time of anxiety you rely on both your family and the family you've built for yourself," Bujalski says.

"It's like an anti-legal thriller. It does borrow a lot of the structure of legal thrillers, even though it obviously doesn't work the way they do. Almost everything a legal thriller would give you, this withholds from you. Those movies are about off-screen conspiracies, and this is more about off-screen anxieties motivating you in your own daily life, and you don't know if they're going to come together or not or if you're just imagining it. It's all the paranoia of a legal thriller without the car chase."

Bujalski, a Boston native and Harvard University graduate, lived in Austin from 1999 to 2000 and wrote "Funny Ha Ha" during that time. He shot "Funny Ha Ha" and "Mutual Appreciation" in Boston, where he also wrote "Beeswax." He returned to Austin in the summer of 2007 to film "Beeswax," which he shot in 20 days on color Super 16 film.

He needed a vintage clothing store that was wheelchair accessible, and he found just that at Storyville Boutique at East 51st and Duval streets. (The shop has since closed.)

"It was a beautiful store and eerily perfect," Bujalski, 32, says. "It was exactly what I had written in the script.

"That location also helped in establishing the palette of the film. Very bright, very poppy colors, with a ton of pinks and greens. A lot of that comes from the store. It's the prettiest film I've ever made."

For this "wildly personal" and "challenging" film, Bujalski relied on the strength of the Austin film community for casting, locations and crew. Co-stars include local filmmakers Kyle Henry and Bryan Poyser and South by Southwest Film Festival producer Janet Pierson.

"A film like this can only get made on a million favors," he says. "I don't know of a better city in America, or the world, for people really having enthusiasm to help out and pitch in." (He likes the city so much that he moved back in early 2008 and this year married local novelist and journalist Karen Olsson.)

A few mixed to negative reviews aside, "Beeswax" has earned positive notices on the festival circuit and in limited release, with major critics calling it "a remarkably subtle, even elegant movie," "wise and wondrous" and "warm and graceful."

Meantime, Bujalski has been turning in drafts for an adaptation of Benjamin Kunkel's novel "Indecision" for Paramount Pictures, which he might also direct, and he and Austin filmmaker Spencer Parsons have sold a romantic comedy to a major studio.

With his "contrarian streak" unruffled, Bujalski says, he wants to keep making movies with idiosyncratic fervor and is working on a new project "that feels like a weird hybridization of personal concerns and something that's a little easier to explain and could be easier to market."

He doesn't easily brook outside expectations of what he should be doing.

"Even after 'Mutual Appreciation,' there was a lot of pressure to 'take it to the next level' and do something bigger. Everybody is interested in career narrative, and sometimes that's frustrating as a filmmaker, because people want to read more about your career than actually watching your film."