A short story, surrounding questions of rivalry and honesty, to whit: when presented with the full-proof method of securing a key victory dishonestly, what should one do. The moral answer is, of course, clear but the reality of the beguiling nature of temptation is something else entirely.
These things are quite improbable, to be sure; but are they impossible? Our big world rolls over as smoothly as it did centuries ago, without a squeak to show it needs oiling after all these years of revolution. But times change because men change, and because civilization, like John Brown's soul, goes ever marching on. The impossibilities of yesterday become the accepted facts of today.
Four men set out to prove their mettle by crossing the bright side of Mercury when it is closest to the sun. A feat which no one has ever done and survived. The odds are against them and they will need all of their expertise and courage if they are to succeed. Even that might not be enough.