London financier David Tait and Sherpa Phurba Tashi face almost impossible odds in their attempt of the world's first double traverse of the mountain – two summits back to back from different sides of the mountain. As the Sherpas achieve a record-breaking early summit, the team members begin to realize what they're up against as they scan the mountain with telescopes and see two professional climbers from Kazakhstan fighting for their lives in the Death Zone. The climbers had followed in the Sherpas' footsteps, but it's late in the day and they're running out of time. Also, Russell finds out one team member hasn't been completely honest about their mountaineering experience.

Russell Brice's team of amateur climbers face their first big test. He's set them a five-hour deadline to climb 2,000 feet to the first high camp at the top of a punishing ice cliff. They've each paid $42,000 to summit Everest, but if they fail the time trial they’re off the team and there are no refunds. Guide Dean Staples is clear about the rules, and is shocked by Betsy's lack of experience. "I think she's quite underprepared because she didn't really know what she was letting herself in for," he says. "You've got to basically be able to get to the North Col in under five hours, and if you can't, then you're not on the summit team."

The climbers from Kazakhstan that the team saw fighting for their lives in the Death Zone the day before are still missing. They radioed for help at 3 a.m. and Russell sent a team of Sherpas to search for them, but there's been no word. Then just after dawn, the radio crackles into life. They've been found in one of Russell's tents, but they're in a bad way.

As Sherpas try to rescue the Kazakhs high on the mountain, the expedition climbers set off for Camp 1. Almost immediately, British climber Rod Baber is in trouble. He's struck by a crippling headache, which could be the first warning sign of acute mountain sickness or even cerebral edema – a swelling of the brain that can kill within minutes.