The raging guitar of a heavy metal song blasts as fire crackles in a burning pickup truck. A gaggle of teens smash the windows, gleefully basking in the warming glow of their destruction. As the truck’s owner runs toward his car, screaming profanities, the hell-raisers sprint off, giggling until they see the flashing lights of police cars speed into view.

This is the energetic opening of UT professor Kat Candler’s feature film, “Hellion,” which is playing at this year’s SXSW festival. One might expect such a vivid snapshot of teen rebellion to come from a younger, angrier voice than Candler — whose appearance and demeanor couldn’t be friendlier — but the inspiration for “Hellion” came from an authentic place: Candler’s own family history.

“All three of my uncles were hell-raisers when they were kids,” Candler said. “My Uncle Frank tells a story of how him and his two brothers set fire to my grandfather’s Jeep when they were very little … That idea of this father and these unruly boys — I loved that dynamic and that father’s struggle with these kids.”

Her uncles’ childhood antics formed the basis for “Hellion,” a 2012 short film that was expanded into a feature and premiered at the 2014 Sundance Film Festival. The film stars newcomer Josh Wiggins as Jacob, a teen struggling to get over his mother’s death.

Candler discovered Wiggins on YouTube after a fellow producer recommended his videos. All that was left was to make sure he had good on-screen chemistry with co-star Aaron Paul.

“I sent Aaron this one callback that Josh did, the pizza scene, he just breaks your heart,” Candler said. “So it came down to Josh and this kid from LA who was great in his own right. Josh walked into the room with Aaron, in his shorts and T-shirt, just totally cool and collected and professional. As soon as the two of them started reading, I remember turning around to my casting director and saying, ‘OK, this is it.’”

Candler balances filmmaking with teaching an advanced narrative production course for radio-television-film students at UT. She got her own crash course in filmmaking at Florida State University, where she studied creative writing.

“I worked in a movie theater from age 15 all through college,” Candler said. “It didn’t pay a lot of money, but I’ve gotten used to that in my entire life. But I got to watch movies constantly … So I’ve always been a huge movie fan, but I didn’t know how they were made.”

In college, Candler was invited to work on a set for the first time by some film students she knew. 

“I just watched the whole process of the [director of photography] setting up lights and the director working with the actors. I realized it wasn’t rocket science to make a movie.”

Since then, Candler has been working steadily, directing four short films in addition to her feature adaptation of “Hellion” in the six years she’s taught at UT. Her students appreciate having a teacher with hands-on experience in filmmaking.

“The biggest benefit of having Kat as a teacher is getting a sense of working with someone who’s from the industry,” said radio-television-film senior Dew Napattaloong. “She’s bringing in all these people who she’s met through Sundance, and they provide us with experience and knowledge. When I do stuff in her class, I feel like I have to meet a standard, and that credibility goes into everything we do.”

The work ethic that Candler’s students exhibit is an inspiration to her. 

“I had this story [of ‘Hellion’] for years, and finally wrote it down back in 2009,” Candler said. “So I was teaching at UT, and I see my kids shooting movies all the time, and I’m like, ‘Why am I not shooting movies all the time too?’ So I handed it to Kelly Williams, my producer, and was like ‘Let’s just fucking make something this summer.’ And that’s how it all started, without any expectations or anything. We just wanted to make a movie.”

For aspiring filmmakers who aren’t in her class, Candler has three lessons.

“Be nice, be professional and work your ass off,” Candler said. “It’s pretty simple, but it’s true. I tell my students, ‘Your job interview started when you started college, because all of us work in the industry. We all know everyone, and it’s a small community. Austin, New York, LA, everybody knows everybody. You want to be the person that we want to work with, and that is a good human being, a professional.”

There’s an energy to Candler when she speaks, which is reflected in the energetic metal songs on “Hellion”’s soundtrack. 

“I kept telling them to turn the whole thing up,” Candler said. “From the very first scene, I just want to punch people in the face.”