Vanessa Hudgens learns what it’s like to have to ask ‘Gimme Shelter’

There were babies everywhere: crying, crawling, pooping. Framed Bible citations and photos of Jesus lined the walls. And no one was using a cellphone.

This is what Vanessa Hudgens saw in 2011 when she arrived at New Jersey’s Several Sources shelter, a safe haven for young pregnant women and new mothers without homes. And it made her very uncomfortable.

“The first thing I did,” the actress later recalled, “was run up to my room, call my mom and go, ‘What on earth am I doing here?’”

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But Hudgens, still best known for her breakout role as a peppy teen in Disney’s “High School Musical” franchise, had arrived on the East Coast looking to be shaken out of her comfort zone. So she reluctantly surrendered her iPhone and spent two weeks living among dirty diapers, going grocery shopping and attending Bible study.

Her temporary hiatus from her more glamorous Hollywood life served as research for her new movie, “Gimme Shelter,” about a pregnant, homeless teen who turns her life around after moving into a home filled with those like her. The film, which opens Friday, is based mostly on the life of Darlisha Dozier, who — after walking 35 miles in a snowstorm — turned up on the doorstep of Kathy DiFiore’s Ramsey, N.J., shelter in 2010, three months pregnant.

But it was not DiFiore who welcomed Dozier on that winter day — instead, she was met by Ronald Krauss, a filmmaker who had taken interest in the non-governmental organization and its 66-year-old founder, DiFiore. After completing a movie about human trafficking, Krauss was searching for his next project, and he’d been spending time at the shelter filming documentary-style footage of the women living there. That’s when Dozier appeared, so grateful to learn there was a bed for her that she smothered him in an embrace.

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“She crushed my heart, really,” Krauss said. “That hug was what made me decide to make the movie.”

The boss, however, wasn’t sold. DiFiore had always been distrustful of the media — particularly talk show producers, who often called the shelter in the hopes of featuring pregnant teens on their programs.

“I was afraid of the work being corrupted,” she said. “For 30 years, it was always quiet — one girl at a time, one baby at a time — pure. I was afraid this would change everything.”

DiFiore was in Los Angeles last week to promote “Gimme Shelter,” scrunched in a booth at a local diner alongside the movie’s writer-director and star. Though it was 80 degrees outside, she was wearing a blazer and had draped an ornate silk scarf around her neck; her seatmate Hudgens, meanwhile, appeared ready to head to Coachella with her floppy sun hat and chunky crystal pendant.

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Indeed, even though DiFiore eventually acquiesced — even allowing Krauss to live in her shelters for a year as he wrote the movie’s script — it’s clear she is still somewhat at odds with Hollywood. When the table’s food arrived, she asked to say a blessing, but Krauss continued speaking about his development of the screenplay.

“We gotta pray!” she insisted. “Dear Lord: Thank you for this food. Thank you for Ron. Thank you for Vanessa. Thank you for Amy. Thank you for ‘Gimme Shelter.’ And we ask that you please help Amy write a terrific story. Amen.”

On set — the New Jersey shelter was used as a real location — DiFiore said daily prayers with the cast and crew. During production, she was both baby wrangler and therapist, helping to look after 23 little children and four girls from Several Sources who appeared in the film.

“The girls would have meltdowns,” she said with a laugh. “Let’s just say they had ‘female problems.’ They’re like, ‘I don’t want to work today! I have cramping!’”

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With “Gimme Shelter” now hitting theaters, some of its once begrudging participants now seem more excited about being on the big screen. On Wednesday, Dozier walked the red carpet at the movie’s New York City premiere, posting selfies with Hudgens on her Instagram account.

“When Vanessa came to stay with us, I thought she was gonna be like, ‘Oh, don’t touch me’ and stuff. But she was really, really nice,” the 22-year-old said via telephone this week, the sound of babies screaming in the background. “People have been saying they don’t recognize her in this role because of the 15 pounds she gained — which is not trying to say she’s fat — but even in her eyes and soul, you see the change.”

Hudgens does look drastically different in the movie: Not only did she add some weight to her tiny frame, but she got rid of her flowing extensions, cutting her hair into a boyish coif. Her character, Apple, is almost always without makeup, has numerous piercings and wears ill-fitting clothing.

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“I remember watching Natalie Portman in ‘V for Vendetta’ when she buzzes her hair off,” Hudgens said, “and you think to yourself, ‘Would I actually do that?’ And the answer always is, ‘If the right role comes, yes.’ And this was the right role.”

The actress, 25, is open about her desire to be taken seriously as a performer, in October telling Marie Claire that she dreams of one day winning an Oscar. But it was only last year that she started to show her acting range, starring opposite fellow Disney veteran Selena Gomez as a good girl gone bad in “Spring Breakers.”

“When you’re part of something so big, people really love holding on to the idea of that person — they become attached to it, and if they see you in a different light it feels like they’ve been betrayed,” Hudgens said. “But I’m 25 now, and I was 16 when I started ‘High School Musical.’ It’s been a really long time now. I’ve evolved as a human being, and with this movie, I hope people see that. But I know that I still have a lot more work to do.”

amy.kaufman@latimes.com