When they make it to the top of K2, Achille Compagnoni and Lino Lacedelli are the first people to set foot on the second highest peak in the world. They take pictures, they raise a flag, but they don’t have the time to celebrate, as they must immediately set off again to return to the base camp. K2 is a treacherous mountain, and many expeditions have attempted and failed to climb it: the Italian expedition succeeds thanks to the skills of its climbers and unprecedented technical support.