ROUGH CUT (NO REPORTER NARRATION) In 2000, a book called "Sarah," about a boy who works alongside his mother as a truck-stop prostitute, was published under the name J.T.
Leroy, apparently an enigmatic author who would make brief appearances wearing blonde wigs and sunglasses.
But the book was actually written by artist Laura Albert, and J.T.
Leroy was a fictional creation portrayed by Albert's friend Savannah Knoop.
Stewart plays Knoop, who binds her breasts and wears masculine clothing to portray J.T.
Leroy at parties and book events.
"What interested me most was just getting to know a person that was so, um, Savannah innately is really creative, really, very honest, present.
Like, when you're with her you can't imagine that she was ever the person that you would go to to create an elaborate hoax with, because she's like the most genuine person," Stewart said.
Dern plays Albert, who encourages Stewart's character to portray the alter-ego she says she created to help deal with a difficult upbringing that included sexual abuse and teasing about her weight.
Dern also said the film's stripped-down production style helped the two actresses form a fast bond.
"We were so lucky that we found each other and found this place that we could inspire each other toward the same character we were inventing and exploring and a love story at its core," she said.
The film was co-written by the real-life Savannah Knoop, along with Justin Kelly, who also directed the film.
Dern and Stewart also talked about their upcoming projects - Dern's second season of the Emmy-winning drama "Big Little Lies," and Stewart's "Charlie's Angels," the latest movie reboot of the 1970s crime caper.
"JT Leroy" is released in U.S. theaters and streaming platforms on Friday (April 26).