[url id="/shows/summit_on_the_summit/series.jhtml"]"Summit on the Summit: Kilimanjaro"[/url] doesn't premiere on MTV until Sunday at 9 p.m. ET, but you can get a sneak peek of the documentary, which follows Kenna and his team's treacherous trek up Africa's highest mountain, right now.

In February, [artist id="1163848"]Kenna[/artist], along with fellow musicians [artist id="2017563"]Lupe Fiasco[/artist] and [artist id="2990655"]Santigold[/artist], actors [movieperson id="188949"]Jessica Biel[/movieperson], [movieperson id="204641"]Emile Hirsch[/movieperson] and [movieperson id="1050687"]Isabel Lucas[/movieperson], and a team of scientists and experienced mountain guides, [article id="1629516"]climbed to the peak of Kilimanjaro[/article] -- some 19,000 feet above sea level -- with the goal of raising awareness about the global clean-water crisis. It's an epidemic that hits close to home for the Ethiopian-born artist.

"When I was younger, my dad pointed out Kilimanjaro on a huge atlas. It stood in my mind as one of the wonders of the world," he said. "This climb is dedicated to my father. As a child in Ethiopia, he lost his brother and lost his friends and family to water-borne diseases. A billion people in the world don't have clean water. I had to do something about it. For me it's personal. I could have been one of those kids. I needed to come up with something that would command attention. And the only thing I could think of that was that massive was climbing Kilimanjaro."

(For more on the climb and the need for clean water, check out the "Summit on the Summit"

Web site.)

During the ascent, things got a little rough, with the climbers braving brutal weather, thinning atmosphere, and dizzying nausea. At one point in the film, Biel explains how the mountain has a way of making even the most brazen climber humble.

"I was sort of irritated that we were stopping so much, I said to one of our guides, 'Can we go a little faster?' " she says. "And then I got a little bit irritated, and I started going down this little area, kind of pissed off, and then I immediately got nausea. The mountain was like, 'Don't disrespect me.' "

Before making the final ascent of the peak, climbers rested at Kosovo Camp, a clearing some 16,000 feet above sea level. Everyone was tired and hurting, but the lure of reaching the top of the mountain was strong, as Lupe Fiasco says during the film.

"Everybody has a different set of variables that affect them on the climb, whether it be what they wear, what they eat, when they go to the bathroom, how much they drink," he laughed. "There's an 80 percent chance that you're going to be uncomfortable. So you kind of have to rewire everything into being comfortable with being uncomfortable ... [you have to] overcome yourself to overcome the environment. Because you can't really fight against nature, nature's going to happen regardless."

And while confidence was high, Kenna was still wary. He knew the toughest part of the trip still lay before them -- the 3,000-foot climb to the summit -- and he was trying to prepare himself mentally. After all, he had been to Kosovo Camp once before, five years ago, and the conditions proved too tough for him to continue on. This time, he promised things will be different.

"You can only be so confident. This mountain has its own mind, and I'll be lucky if I get to the top, I'll be thankful if I get to the top, but I'm not underestimating what's ahead of us," he says. "I'm worried, because people are sick, people have knee problems, people are cold, it's all mental at this point. I don't know how well people are going to be able to pull it off, considering they've never done it before. Last time I was here, that's what happened to me. It wasn't that I was sick, but I could've been more focused, and allowed myself to be sick until I got there. So, I've charged my brain this time, if I vomit or if I trip or if I have frozen toes and feet when I come off and I have to get 'em amputated, I'm going."

Don't miss "Summit on the Summit: Kilimanjaro," airing Sunday at 9 p.m. ET on MTV. And find out what you can do to help solve the global water crisis now at the "Summit on the Summit" Web site.