Seven men were somewhere on the upper slopes of Denali and nobody had heard from them since a single radio call from the summit. Five survivors were pinned in their tents three thousand feet below, so battered by the wind that four hours of climbing gained them only a few hundred yards. In 1967 there was no rescue service on the mountain, no aircraft that could fly in those conditions, and no way for anyone to go up and look.

Which is how a group of climbers with no connection to the expedition became the only people who could find out what had happened. A Mountaineering Club of Alaska team, a bush pilot circling in a Super Cub, and a note wrapped around a rock and dropped onto the ice.

What they found at high camp was a collapsed tent and a body still gripping the tent pole. Below Archdeacon's Tower they found two more men, one sitti ...