On June 8, 1924, George Leigh Mallory and Andrew "Sandy" Irvine were last seen climbing toward the summit of Mount Everest. Clouds soon closed around them, and they vanished into history. Ever since, mountaineers have wondered whether they reached the summit twenty-nine years before Edmund Hillary and Tenzing Norgay.

On May 1, 1999, Conrad Anker, one of the world's strongest mountaineers, discovered Mallory's body lying facedown, frozen into the scree and naturally mummified at 27,000 feet on Everest's north face. The condition of the body, as well as the artifacts found with Mallory, including goggles, an altimeter, and a carefully wrapped bundle of personal letters, are important clues in determining his fate. Seventeen days later, Anker free-climbed the Second Step, a 90-foot sheer cliff that is the single hardest obstacle on the north ridge. The first expedition known to have conquered the Second St