Climbers arrive at base camp and quickly learn the dangers of the mountain.

Hundreds of climbers at Advanced Base Camp prepare for the climb.

Russell splits the expedition in two for the five-day summit assault.

The teams race against the clock as they run out of time and air.

Some climbers reach the top, but then get caught in a line to descend.

Struggling climbers suffer from "summit fever" and refuse to turn back.

Some climbers aren't quite ready for the rigors of Everest.

The team has five hours to climb 2,000 feet to the first high camp.

At 24,500 feet, climbers struggle with dehydration and exhaustion.

The expedition leaves Base Camp heading for the summit. David Tait and Phurba Tashi are within hours of the summit, but even if they make it, they're only a quarter of the way through their challenge.

As Team One set off for the summit, Tim is last out of camp and taking his time on the first leg to Camp One. When Tim eventually arrives at Camp One, Russell tears into him over the radio and threatens to throw him off the team.

Team One fights its way to Camp 4 at 27,500 feet, inside the Death Zone.

Five miles high in the Death Zone, Team One set off for the summit at midnight in minus 30 degrees, filmed by high intensity infra-red Sherpa Cams. But before the sun rises, Tim Medvetz falls and snaps two bones in his left hand. He's in big trouble.

Day 2 proves exciting as asthmatic Mogens Jensen leaves Camp 4 on his fourth attempt to climb Everest. Also on his way to the top is 71-year-old Japanese climber, Katsusuke Yanagisawa, who will be the oldest person ever to summit if he makes it.

Ice falls and avalanches pose a constant threat as the mountain warms.

John Golden and his guide defy the weather and strike out for the top.