Claire Danes does her homework for HBO’s “Temple Grandin”

To capture the unique inflections of Temple Grandin, an autistic pioneer whose life is the subject of a new HBO film, Claire Danes spent weeks listening to recordings of Grandin on her iPod, practicing her gruff abruptness. She became so immersed in “Temple-speak,” as she put it, that when she saw Grandin recently in Los Angeles to promote the film, “I slipped immediately back in Temple mode,” the actress admitted.

“It was very embarrassing,” Danes said, shaking her head at the recollection. “It’s like you go to the South and start speaking like people there. Not OK, not appropriate!”

But it’s not surprising that Grandin is lodged in Danes’ muscle memory. Portraying the animal behavior scientist who is a hero in the autism community was her most demanding role to date, the actress said, one that required intense research and practice.

“I didn’t want to do an impression,” said Danes, who met with Grandin, studied her books and worked extensively with a dialect coach and choreographer to shape her performance. “She’s wired in such a fundamentally different way than I’m wired that I couldn’t just slip casually into her.”

That’s exactly what director Mick Jackson was counting on when he pitched Danes on the idea of playing Grandin, who shook up the male-dominated cattle industry with her demand for a more humane system to slaughter livestock.

“She was my first choice always, because she’s so fierce,” Jackson said. “She is so disciplined, so brave and so focused. That obsession with getting it right is very like Temple.”

Falling in love

But in many ways, Danes was a surprising choice. The 30-year-old actress is best known for gossamer romantic roles in films such as “Romeo+Juliet” and “Evening” as well as her portrayal of teenager angst in the cult television show “My So-Called Life.”

“I think it’s my age, but I’m constantly playing people who were falling in love, and that was the catalyst for change every time. Which is great -- I mean, I love falling in love too,” said Danes, who recently married her “Evening” co-star Hugh Dancy. Dressed in faded black jeans and a striped shirt, the actress sipped a bowl of chicken soup at a SoHo cafe near her home on a recent blustery morning. “But I was getting a little bored of that. There are other human experiences, you know?”

Playing Grandin, Jackson promised, would be “an opportunity to work without a safety net.”

“When you have a really gifted actress like Claire, she knows how to underplay the emotion,” he said. “But Temple has these volcanic emotions: fear and panic, joy and manic elation. I said, ‘You can’t trust your instincts. You have to try to see the world the way she does.’ ”

In Grandin’s view -- which was the one most important to the actress -- Danes succeeded.

“I was like, I can’t believe this beautiful blond lady became me in the 1960s,” said the author and scientist, who originally envisioned Sigourney Weaver playing her. “And the thing that amazed me was that if you didn’t know that Claire was playing me and there was no credit, you’d never know it.”

Perhaps that’s why in its marketing of the movie, HBO has made a point of spotlighting Danes’ presence, hoping to bring some star power to a rather esoteric subject.

“When people do start to appreciate who she is, they find it riveting, without fail,” Danes said of Grandin’s life. “But just getting them to see it might be a bit of a struggle. It’s hardly boy meets girl. It’s girl meets cow.”

Thinking in pictures

“Temple Grandin,” which debuts Saturday, focuses on Grandin’s youth and early years as a scientist when she labored to get the cattle industry to take notice of her inventions. Because of her autism, Grandin “thinks in pictures,” as she says, an ability that gives her insight into how animals view the world. She persuaded the industry to adopt her reforms in the face of mockery and outright hostility. Along the way, Grandin struggled with the limitations imposed by her autism: her terror of sliding glass doors, her aversion to being touched, the panic attacks triggered by overstimulation.

Now a leading figure in the cattle industry and a professor of animal science at Colorado State University, Grandin’s success has made her a household name in the autism community.

“I just didn’t want to disappoint her and the people who care a great deal for her,” said Danes, who was relieved when Grandin offered her a rare hug at the end of their first meeting. “It was like the permission I needed to take this on.”

Danes worked on capturing Grandin’s voice in private, refusing to let Jackson hear it until the first day the cameras were rolling. Throughout the shoot, she wouldn’t watch any playbacks of her performance.

“I really had to protect myself from any self-consciousness as much as possible,” Danes said.

What helped in channeling Grandin’s unrestrained yearning for knowledge was Danes’ own tendency to be “really nerdy,” she said with a laugh. “I was just always that annoying girl in class with her hand up, so I just let that bloom.”

After this performance, Danes can no longer be looked at simply as an actress best suited to romantic roles, Jackson said.

“It will move her into Meryl Streep-Robert De Niro-Charlize Theron territory,” the director said, “someone so sure of herself as an actress that she doesn’t have to have a sense of whether she looks good or bad. She just does what is right for the movie.”

Danes cringed at such praise.

“The level of that accomplishment is so incredibly modest compared to the level of her accomplishment,” the actress said of Grandin. “She was extravagantly brave at almost every moment of her life.”

[email protected]