Thousands of wild horses roam free in the western United States, protected and growing in population. But under pressure from ranchers and conservationists who complain the mustangs are destroying cattle grazing land, the Bureau of Land Management has corralled 50,000 equines in holding pens in government facilities, awaiting adoption.

To bring attention to this problem, Ben Masters and his buddies Thomas Glover, Jonny Fitzsimons and Ben Thamer hatched a plan: they would adopt and train 16 wild mustangs in preparation for a five-and-a-half-month ride from the Mexican border north through Arizona, Utah, Idaho, Wyoming and Montana to Canada, passing through the Grand Canyon, Yellowstone and Glacier National Park. "Unbranded," which premieres in theaters and on VOD services on Sept. 25, documents their journey through challenging terrain and harsh conditions, with breathtaking cinematography by director Phillip Baribeau and Korey Kaczmare.

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"The idea started when we were drinking tequila," says group leader Masters, who explained how it progressed from there, what the experience meant to him, and what he learned from it.

MNN: Why did you want to go on this adventure?

Ben Masters: Certainly we wanted to inspire wild horse adoptions, but the fact that there is still a stretch of largely undeveloped land all the way from Mexico to Canada that you can still ride horses through is an appeal that I couldn't resist. I don't know if that route will exist in 10, 20, 50, or 100 years, and I wanted to see those landscapes now. The timing was also right in my life. I'd just finished college and wanted to do something that wasn't "normal" by society's standards and to learn more about myself. Getting to spend five months in the backcountry without cell phone reception also really gives you a huge amount of respect for nature and land stewards.

Ben Masters rides his mustang Luke while leading another horse in the film 'Unbranded.'Ben Masters rides his mustang Luke while leading another horse in the film 'Unbranded.' (Photo: Cedar Creek Productions)

How difficult was the training process? Were any of the horses untrainable?

We used two professional trainers, Jerry Jones and Lanny Leach, to help us select the horses for the trip and to put the first 30 days of training into them. I'm glad we used professionals because training wild horses can be extremely dangerous and the first impressions those horses have with humans are incredibly important. After thirty days of training, eight of the 11 horses that we adopted could be saddled. The remaining three weren't progressing fast enough, or they were too dangerous. We decided to let them go to a big ranch in West Texas where they'll live out the rest of their lives.

What advantages do mustangs have over domesticated horses?

Mustangs grew up in the wild so they have been walking on difficult terrain their entire lives. They avoid mud that's too deep, are careful on steep trails and are perfectly adapted for mountain travel. Mustangs' hooves are incredibly tough, and they're survivors that can eat just about anything and continue to be healthy and not lose weight.

Were you scared at all on the trip? Some of the terrain was pretty hazardous.

Yes, I was definitely scared during parts of this adventure. I was scared Phil snapped his femur when he took a crushing kick, that Dinosaur would die when he fell off the cliff and that we'd never find our horses when they ran 40 miles away. We had human injuries, horse injuries, fatigue, dangerous terrain, dangerous wildlife and a host of other things that can injure someone or put a halt to the trip.

Did you gain a new appreciation of Mother Nature?

Yes. Traveling 3,000 miles and seeing the land unfold at three miles an hour allowed me to soak in many of the incredible sights across the American West. Being from Texas, where it's 95 percent private land, I didn't realize how vast some of the public land areas were in the West and was blown away by the ability to truly get lost in the mountains and travel hundreds of miles without coming across a lot of civilization. That being said, we crossed an insane amount of fences, found it very difficult to stick to trails and not roads, and the biggest dangers were human made obstacles like highways, tunnels, train tracks and cities that we had to go through.

The group of 'Unbranded' adventurers traverses a canyon pathThe group of 'Unbranded' adventurers traverses a canyon path. (Photo: Cedar Creek Productions)

What was the best part of the experience? The worst? What were your favorite moments or highlights?

My favorite memory was fly-fishing with my mustang, Luke, on my birthday deep in Montana's backcountry. Luke and I rode out into the middle of a lake and caught a beautiful cutthroat trout. He let me cast off his back, reel in a fish, and never once tried to panic or get out. Your horse has to have a lot of trust in you for that to happen, and it was a really cool moment. The worst moment was when Jonny decided not to finish with the team.

Was there anything you'd have done differently?

I would've stopped more often and tried to soak in the small moments.

Did you plan to make the film from the get-go? How did it come about?

Yes, I wanted to document the ride for my personal memory and to showcase the mustangs. We used Kickstarter to raise $171,000 in 45 days and used that as seed money to launch the film. Through the Kickstarter, we met [producers] Cindy Meehl and Dennis Aig, and we had a dream team. We're really fortunate that the right people came along at the right time.

Ben Masters leads the group in 'Unbranded.'Ben Masters leads the group in this photo from 'Unbranded.' (Photo: Cedar Creek Productions)

What were the most important points to convey in the film?

I wanted to show people how many big landscapes still exist in the American West, build pride in them and make people feel like keeping open landscapes is important. I also hope "Unbranded" inspires other people to take their big journey whether that's a horseback ride, backpack trip, kayak, climb, starting a business or whatever it is that is your dream. I also hope that "Unbranded" shows viewers that the wild horse issue isn't black and white and that keeping wild horse populations at the appropriate level is crucial for the health of the rangeland and everything that relies on it. Because wild horses are such beautiful, majestic and spiritual animals, reducing their population is very difficult because there are a lot of emotions, love, and affection towards them.

Is adopting these wild horses practical, since it takes so much time and effort to train them?

Yes, I have six adopted mustangs and they are wonderful fantastic horses. I would trust an inexperienced kid to ride three of them.

The cast of 'Unbranded' make their way across the rangeland with mountains in the horizonThe cast of 'Unbranded' make their way across the rangeland with mountains in the horizon. (Photo: Cedar Creek Productions)

"Unbranded" points out the opposing sides in the wild horse issue. Where do you stand in the debate, and why? What is the solution to the issue?

In an ideal situation, volunteers would aggressively use hormone darting on wild horses to slow their population growth so that the amount of horses that needed to be rounded up off the range would equal the adoption demand. I also think the Bureau of Land Management needs a better website and PR strategy to get people to want wild horses. The problem that the BLM has is that they don't have any money to put towards darting horses on the range because they spend all of it on a $45 million feed bill stockpiling 50,000 wild horses and burros that don't have a home. They're out of money, out of places to hold horses and populations on the range are almost twice the appropriate management level. My fear is that if we don't get the population under control, the wild horses will degrade the landscape and eat everything. Then, when a bad drought or snowstorm hits, the wild horses, wildlife, songbirds, deer, reptiles and everything that depends on a healthy rangeland will suffer from our poor management practices.

What did you learn from the experience? How did it change your life?

I learned a lot about myself on the ride itself and also during the editing stage. It's a rare opportunity for someone to get to see themselves on film as other people see you in real life. I saw good qualities in me and not so good qualities that I need to work on! I learned that good communication is crucial and that unfortunately people can't read my mind. I learned that when horrible things happen it can always be worse. And I learned that the way people treat their animals often gives you insight into their character. Yes, the trip changed my life, and it has already opened numerous doors for me.