With a bit of a midlife crisis going on (43?? still a youngster!) Jim treats himself to a simulation chamber, that is installed in the garden. Beauty of this is that by taking out a package, he can climb in there and wire himself up and spend several weeks on a virtual Everest, getting ready for the climb of his life.
Or in fact, the climb of his death, as this simulation isn’t (not really addressed in the story) 100% virtual, as injuries occurred whilst in the sim translate to the flesh and blood back in the sim-tank. And of course Jim gets in trouble on Everest, and has to find the inner wherewithal, and help from some other sources, to avoid ending up another frozen corpse in a crevasse.