The theories of what might have happened to Sandy Irvine during and after the fatal attempt to climb Everest in 1924 are even more speculative than those that ponder George Mallory's fate. With Mallory, at least we know his final resting place and we have some evidence, however conjectural, of what happened to him in his final hours.

One possible sighting of Irvine's body was made during a 1975 Chinese expedition up the North face of Everest. Climber Wang Hung-bao found what he described as an "English dead" at 27,000 feet. Although the news wasn't released because of China's closed-door policy Hung-bao was able to describe his find to a Japanese climber shortly before his death on the North Col. He described the body as being drawn up in a fetal position dressed in old-fashioned clothing and with a hole in its cheek.

This body doesn't fit the description of George Mallory's body as it was found in 1999. George was by all evidence still in the position in which he had died, laying on the mountain, arms stretched out and fingers dug into the scree. Did Hung-bao find Mallory's body or was it Irvine's body instead?

Conversely Chinese climber Xu Jing, claims to have found Irvine's body in a sleeping bag wedged in a crevice between two steep cliffs at 27,300 feet on the North East Ridge of the mountain. This is above the slope where Mallory's body was found in 1999.

Mallory's body was found with a broken rope around his waist and the supposition is that he and Irvine were traveling together, when Mallory's rope broke and he fell to his death. Irvine now poignantly alone on the mountain took refuge in his sleeping bag, fell asleep and never woke up. As there were two sleeping bags found in the men's tent at camp, it's not clear why Irvine would have been carrying a spare sleeping bag while Mallory was apparently not.

There are still other theories that may provide insight into what may have happened to Irvine. These theories do not take into account Jin's sighting of a body. One is simple; Mallory and Irvine were traveling together (on ascent or descent, making to the summit or not), and both fell to their deaths (perhaps due to the snow squall which Noel Odell reported) and Irvine's body is somewhere near where Mallory's was found.

Another is that the two men made the summit or not, but again both fell from the North East Ridge. Irvine's body landed on a lower ridge (ledge) where he either died immediately or perhaps lingered, injured and unable to move. The rope holding them together snapped and Mallory continued to fall. This "long fall" theory is hampered by the fact that though he died where he fell, Mallory's body is not badly broken up given the distance that he would have fallen. And it is apparent that given his outstretched arms and fingers dug into the scree that Mallory apparently lived long enough to attempt to stop his own fall. This does not seem likely given the distance he would have fallen to reach the point where his body was found.

It is possible that Xu Jing's report is correct of course and that Irvine's body is somewhere on the upper slopes (27,300 feet) of Everest still in his sleeping bag. It is possible that the two men, having either made the summit or having turned around at the second step became separated in the darkness (perhaps due to the rope binding them together breaking) and lost from each other. Mallory struck out across the face of the mountain (possibly along the yellow band) looking for Irvine when he slipped and fell to his death. Irvine for his part would have continued alone, perhaps in an attempt to reach camp and relative safety from the cold. However unable to continue he is forced to bivouac on the slopes of Everest and dies of exposure. It possible that the body found by Jin indicates this scenario or another like it.