Final answer:
George L. Mallory and Andrew Irvine were early British mountaineers who vanished on Mount Everest in 1924. Their ultimate fate is unknown, though Mallory's body was found in 1999.
Step-by-step explanation:
George L. Mallory and Andrew Irvine were early British mountaineers who disappeared on Mount Everest in 1924. Their fate became one of the greatest mysteries in the history of mountaineering. They were part of an expedition that attempted to be the first to reach the summit of Everest. Although it's still not confirmed if they reached the summit before they vanished, Mallory's body was eventually found in 1999, but Irvine's remains have not been discovered. The pair's disappearance remains a subject of speculation and intrigue in the mountaineering community to this day.