Rob Hall's friend and climbing partner Gary Ball died in his arms on 8,167m Dhaulagiri in October 1993. Ball had come down with a case of high-altitude pulmonary edema (HAPE) at six and a half kilometres altitude. Despite this loss, Hall went on to lead a highly successful expedition to Mount Everest in 1994 with Ed Viesturs. This was Hall's fourth summit of Everest. In 1995 Hall's expedition had to turn back because of bad weather as they neared the summit. In May 1996 Hall and a group of climbers made it to the summit of Mount Everest, but he and several other members of his party died on the way down. This event had a noted impact on media, appearing in various books and films. The disaster became very well known, with ten million people reading about it in the book Into Thin Air, written by Jon Krakauer (who was actually on the expedition) and hearing it referenced in a highly acclaimed IMAX film, shot during the same disastrous climbing season, although the filmmakers summitted later in the season.