Transcript for In Blackfeet Nation, a boxing club is fighting to save Native American women’s lives
Reporter: For boxers, the gym is a sacred space. Inside, amongst the orchestra of work, the outside world dims. You can find yourself, your strength, and at this gym with these girls, that takes a whole new meaning. It gives you like this sense of empowerment. It's bringing out someone that you never thought you would be. I tell all my kids in the boxing club, there's your psychologist right there. Whatever's baring you, you take that bag until you can't hit it anymore. Reporter: Frank kip is the man in charge. Before he opened this gym in 2003, he worked as a probation officer here on the blackfeet reservation in Montana. I'll never forget one little girl who was raped and the guy beat her up. And she had black eyes. I called up. And the rape kit was lost. And I started thinking, what can we do better? How can we keep these girls from harm's way? The only answer was this club. Reporter: In the new film "Blackfeet boxing", it documents how kip and his club help indigenous girls to protect themselves by getting in the ring. What motivates frank to train these girls to do what they do? Fight is such a rich and deep word. It can be seen very negatively and it can be seen very positively. For franks, he understands the power of that nation. What he wants most is to develop the arsenal of self-esteem, determination and protection. And that's why frank does some things which are incredibly unconventional as a boxing trainer. He showed us how to break somebody's arm, take somebody's eye out. I said what does this have to do with boxing? He said I'm teaching you to defend yourself on the streets. Reporter: A sprawling reservation near glacier national park. The beauty and resiliency of those who call it home belies generations of trauma that today manifests with high drug abuse rates and crime. More than 100 indigenous women and girls have gone missing or been murdered since 2018. Just an epidemic across swaths of America. At least 4,000 missing in the United States, only a quarter of those logged in Namus. What do I teach you to do? Fight back. Why? Because it might be the last time. It might be the last time we see you. Reporter: You've encountered and told a multitude of stories of phenomenal coaches, people who make a difference in so many young people's lives. People won't know frank kip's name the way they know Mike krzyzewski or of Nick Saban or any of the legendary and great coaches, but I will tell you this. He has had every bit as great an impact on the lives that he touches. Reporter: If there's one crime on the reservation that hits closest to home, while serving as a cautionary tale, it is the 2017 unsolved disappearance of Ashley Loring heavyrunner. There was like a cloud, and everybody felt this like, "Will it be me next"? When Ashley went missing T brought a huge influx into the gym. Reporter: One of those girls, Kennedy. She's tough. You look at her eyes, you know she's a fighter. She's war-like. All the boys that I sparred, they all got scared. They all didn't want to spar me. She could be an olympic champion. She's got the gift. Mimi actually received several academic scholarships. She's not just promising inside the gym but promising academically. Reporter: Mimi's fright future similar to Ashley's. Everyone time I think about her, I think about her smile. Everybody wanted to talk to her. She was beautiful and outgoing. Reporter: A loving sister. A doting godmother. A star athlete in high school, known for her contagious smile. She excelled at college, until her light began to dim. She'd begun dabbling with drugs and running with an older crowd, in part to numb the pain of losing her beloved grandfather. And then she vanished in June 2017. She told me she loved me and tried giving me a hug. I didn't give her a hug. And then she left through the and that was the last time I saw her. Reporter: For nearly two years, "Nightline" followed Ashley's family on their desperate journey to find their loved one. Oh, my gosh. Reporter: Leading the charge to bring Ashley home, her older sister, Kimberly. From searching the vast reservation to even testifying on capitol hill. Kimberly is committed to her sister. Our girls, our people and our men are important. Reporter: It's been three full years now since Ashley disappeared, and the family still has no answers and no Ashley. You've been dogged through all of this. You have been your sister's boldest advocate, and, you know, I have sisters myself, but everyone would want you for a sister. It's Ashley's love that makes me strong. Reporter: We're revisiting Ashley's story, because these girls are so inspired by her, driven by her and determined to fight in Ashley's name. I'm really happy that they wanted to fight, they wanted to keep going, and then that Ashley's story inspired them, because it should, because back home all the girls should be strong. All our girls should be headstrong as well as being able to fight, because we are fighters, and we come from a tribe that are fighters. Reporter: The blackfeet nation are warriors. Yes, we are warriors. Glory is forever. Reporter: In Ashley's memory, now a group of warriors, taking matters into their own hands, and for kip's daughter Donna, also fighting for something greater. For each fight, I write mmiw. It's so powerful when you see a girl just wise beyond her years and seeing her prepare for this huge match and wrapping her hands and writing "Mmiw", missing, martyred indigenous women. That's the thing she's going to dedicate her life to. The blackfeet nation! Donna kip! Full film is available now on espn.com. And on the ESPN app.
This transcript has been automatically generated and may not be 100% accurate.