AS AUGUST ROLLED on at the base of Nanga Parbat, the days grew shorter and the nights chillier. In the meadows, the sheep and goats bent to the grass, packing on the fat, and in the mess tent it was pretty much the same: nonstop chomping. If the tension was mounting, it was hard to see. What was apparent, though, was that Anderson, with his pierced ears and nipples, and the straitlaced House were getting along like old friends.

But they weren't old friends, really, even though they'd first met in Alaska in the late nineties and had done some work together as American Mountain Guide Association instructors. (While Anderson still works full-time as a guide, House's main employment these days is as an "ambassador" and product tester for Patagonia.) Over the winter, House had, in Anderson's phrase, "cold-called" him about the Rupal climb. Amazingly, until their rounds of acclimatization on Nanga Parbat, the two had never done any serious climbing together.

"I think some of our strengths are complementary," Anderson told me. "I can keep it rolling pretty much forever, albeit slowly. On the other side, Steve has a lot of fortitude, and he's smart at figuring things out. I don't know—I might balance out some of his eagerness."

House, too, seemed cautiously optimistic. "An alpine partnership is probably one of the most challenging things in the world," he said. "It's not easy to trust like that. Messner and Habeler, Boardman and Tasker—there haven't been a lot. It's rare."

Then again, the two have a lot in common. Both grew up in the West—House in eastern Oregon, Anderson in central Colorado. Both are smart and thoughtful, House with a degree in environmental science from Olympia, Washington's Evergreen State College and Anderson a University of Colorado graduate in architectural engineering. And both possess an innate sense of style that extends to more than just climbing. "I'm just a dirtbag," Anderson says, "but, still, I hate surrounding myself with cheap plastic stuff."

Anderson got into mountaineering via a teenage interest in steep backcountry skiing. For House, the path had a lot to do with his decision to spend a year studying abroad after graduating from high school in 1988. His father, Don, a former accountant who still lives in LeGrande, Oregon, with House's mother, Marti, a retired teacher, had to pull out an atlas to find the country to which his son was assigned: Slovenia, a tiny, mountainous enclave at the eastern end of the Alps. House's outlet there was climbing—practically the national sport. He joined a local outing club and spent every weekend in the mountains.

"I think he learned from the Slovenian climbers, who are accustomed to much harder living than we soft Americans are, what was 'normal' in the mountains," says Mark Twight, a climber, writer, and alpine-style hardliner who's known House since 1998.

In 1990, after his freshman year in college, House joined some of his Slovenian clubmates on an expedition to Nanga Parbat's Schell Route, just a few miles west of the Rupal Face. The bid was successful, placing two climbers on the summit, but for the 20-year-old House, it ended with him vomiting in the snow at Camp II. "I left very humbled," he recalls. "I was so undergunned I had no business being here." At the same time, he adds, "it's not surprising I conjured it as a dream."

After graduating, House moved to Mazama, Washington, and started work as a climbing and backcountry-skiing guide in the North Cascades, often in tandem with his college sweetheart, Anne Keller, whom he married in 1995. (The two divorced in 2004.) Over the next ten years, he completed nearly 30 expeditions in Alaska. His first big route, in 1995, was a fast and light assault on Mount McKinley's 4,400-vertical-foot Father and Son's Wall, which he climbed with another guide, Eli Helmuth, in 33 hours.

It was in Alaska, a year later, that House met Alex Lowe, who invited him to a frozen-waterfall-climbing "gathering" in Cody, Wyoming—an experience that House says was "pretty much like Larry Bird asking me to shoot a few hoops." In Cody, mixing with a dozen of Lowe's friends, the elite of the alpine world, House made a strong first impression.

"There were new routes to climb all over the place, and Steve and I put up a couple one day," recalls Bill Belcourt, a manager at Black Diamond Equipment. "Steve had an easy grace that was beyond his years. He showed a lot of patience and control, and there was nothing flashy about his climbing style, something that showed a profound level of maturity. I liked to say, 'Steve climbed like an old guy.' "

Soon, House found himself climbing big routes with alpinists whose pictures he had once cut out of magazines: Barry Blanchard, Scott Backes, and Mark Twight—a close-knit group of alpine-style purists. In 1999, he led the charge on a new route called M-16, on Howse Peak, in the Canadian Rockies. The crux was an insanely fragile 200-foot tongue of vertical ice that was one to two feet wide and in places about half an inch thick. House took three and a half hours to negotiate the pitch, then fixed an anchor with eight ice screws to belay his partners. "It was as hard as anything I've ever done," he says.

Twight, whose angry climbing screed "The Rise and Fall of the American Alpinist" had turned House on when he read it in high school, became a mentor. After he, Backes, and House completed the most notorious climb of the 2000 season, a 60-hour, 9,000-vertical-foot route on McKinley called Czech Direct, he told House that his own career was winding down, adding, "You must know deep inside that this responsibility will pass to your shoulders sometime."

House hated the pressure that came with such pronouncements. At the Ouray Ice Festival a few years ago, he stood up to give a slide show about the "progression" he saw in his own climbing career. As he was trying to explain why he'd recently shifted his focus to the Himalayas—"Basically, there was no terrain left in Alaska that was big enough"—a British rock climber who'd had a few beers loudly called House an "arrogant cunt." House was stunned but gathered himself and went on.

"I was unprepared for the burden of proof being directed at me," House says of his rise to prominence. "I've thought about just not responding, but I feel like if I don't, I don't know who will."