If rock climbing is a cult, then Peter Mortimer makes its classics. His Boulder production company, Sender Films, has been churning out visual adrenaline for rock jocks since its founding in 1999. This year, its fan base hit a growth spurt thanks to the studio’s latest—and widest—release. The Dawn Wall, which follows Tommy Caldwell and Kevin Jorgeson’s attempt to free-climb a supposedly unconquerable route on Yosemite’s El Capitan, won the Audience Award for Documentary Spotlight at Austin’s SXSW Film Festival in March. Then, in September, 70,000-plus theatergoers in the United States attended one-night only viewings, and stellar reviews earned the film an encore screening. All told, The Dawn Wall has made about $2 million at the global box office. With Sender’s 20-year anniversary arriving in 2019, we sat down with Mortimer to ask how he found a fingerhold in the film industry—and if he’s topped out yet.

Name: Peter Mortimer
Age: 44
Occupation: Founder and president of Sender Films
Accolades: Sender Films has won two Emmys

Photo by Claudia López

5280: How did Sender Films get started?
Peter Mortimer: I graduated from Colorado College with a geology degree, but I took a video class my last semester and loved it. I’d grown up climbing, so I decided to make this film, Scary Faces, starring a high school friend, Zac [Barr, now head of production at Sender Films], about climbing a route in Eldorado Canyon we’d always dreamed of as kids. And I truly believed it was one climbing video and I would never make another.

What changed your mind?
Our premiere at the Boulder Theater. I thought nobody would come, but it sold out. There was a line outside the theater wrapping around a full square block. I realized I’d tapped into this niche.

How did your Reel Rock Film Tour begin?
Josh Lowell [co-founder of Big Up Productions in New York] was one of the few making climbing videos back then. We loved theatrical screenings, but we didn’t always have the bandwidth to tackle the bigger films we wanted to make. So [Lowell and I] came up with the idea to basically combine three to six films of varying lengths into one annual tour. I think the first year, 2005, we did maybe 50 shows. Now we do about 500 cities around the world.

Photo courtesy of Red Bull Media House

What made you decide to go big with The Dawn Wall?
It’s an outgrowth of our Reel Rock films, but the story is much richer. We spent seven years filming, then another three years after they did the climb just putting it together. The relationship between the characters—the sacrifices they make for one another—is deeper than anything we’ve ever done before. This is the best film that we’ve made.

What’s Sender Films’ next big project?
We found this young Canadian alpinist, Marc-André Leclerc. Some of my badass climber friends were like, “This guy is the best alpinist ever.” We filmed with Marc for three years, off and on, and then we released him back into the wild. About six months later, when Marc was 25, he died in Alaska. He and his partner were just a few hundred feet from their base camp, and they were killed by a freak avalanche.

How does that impact the movie you’re making?
It’s made us feel like the story is more important to tell, so it’s our next feature film. We captured this special time in his life, and we want to get it right. We hope to release it in the spring of 2020.

Speaking of the future: 2019 marks the 20-year anniversary of Sender Films. Made any big plans?
I’ve been wanting to create a channel where you can pay a flat fee and watch everything we’ve ever made. We have about 40 hours of films and shorts out there. That could be a really cool way to celebrate.

This article was originally published in 5280 December 2018.
Angela Ufheil
Angela Ufheil
Angela Ufheil is a Denver-based journalist and 5280's former digital senior associate editor.