Book request: This must be a golden-age SF short story. I read it as a kid, translated into Russian, probably later 80s or early 90s but the story must be older than that. I remember that some kind of personal confrontation happens on a different planet. The distinctive landscape feature are these big dust-filled sinkholes, in which a person could fall in and get lost forever.For some reason, the hero, and, possibly others, are using plastic flesh or some kind of artificial flesh - I don't remember if this is for impersonating others or for some other reason. In the end the hero wins. He uses the sinkhole to hide in. He is badly burned. The ending is something along the lines, "He gathered all pain from all over his body mentally into a single point, then lifted that point of the body. When they found him, half of his face was horribly burned. The other half was smiling blissfully."

Matching book description: Otto McGavin is peacefully idealistic by nature, an Anglo-Buddhist, who seeks employment with the Confederacion because he believes in its mission to protect human & nonhuman rights. The only problem is that the Confederacion needs him as one of its twelve Prime Operators for its secret service, the TBII. The TBII wants him as a spy, thief & assassin. It's not, of course,  Otto McGavin is peacefully idealistic by nature, an Anglo-Buddhist, who seeks employment with the Confederacion because he believes in its mission to protect human & nonhuman rights. The only problem is that the Confederacion needs him as one of its twelve Prime Operators for its secret service, the TBII. The TBII wants him as a spy, thief & assassin. It's not, of course, a problem for the Confederacion, which simply uses immersion therapy & hypnotic personality overlay for Otto's training, then sends him out in deep cover, encased in plastiflesh, on a variety of dangerous missions on a number of bizarre worlds. But for him, it's a different matter: what he has to witness & what he's forced to do take a terrible toll. Always he returns to his original self--his conscience stabbed by the memory of all those he'd killed in the service of interstellar harmony. ...more