The Shadow of the Torturer by Gene Wolfe

Justice is a high thing, and that night, when I lay beside Dorcas listening to the rain, I was young, so that I desired high things only.  That, I think, was why I so desired that our guild regain the position and regard it had once possessed.  (And I still desired that, even then, when I had been cast out of it.)  Perhaps it was for the same reason that the love of living things, which I had felt so strongly as a child, had declined until it was hardly more than a memory, when I found poor Triskele bleeding outside the Bear Tower.  Life, after all, is not a high thing, and in many ways is the reverse of purity.  I am wise now, if not much older, and I know it is better to have all things, high and low, than to have the high only.

Severian is a journeyman in the Guild of the Torturers in the Citadel of Nessus.  His guild is widely loathed; torturers rarely leave the Matachin Tower where they are stationed because they are suspected, spit upon, distrusted.  But still, they are a necessary part of the fabric of life in Nessus, the executives of justice who carry out the will of the mysterious Autarch who rules somewhere from his house in the northern wilderness.  For that reason, Severian is committed to the torturer's life, even as a raid early in his life by the rebel Vodalus suggests that justice has other forms and functionaries.  That is, until he shows mercy to a high-born, beautiful, and intelligent captive named Thecla who is caught up somehow in the Autarch's campaign against Vodalus, and is expelled from the tower.  He's not quite stripped of his membership in the guild--like bureaucrats in our world, they shy away from controversy and disrepute--but he is sent to serve as an executioner in a remote town.

The torture that is prescribed for Thecla is a machine called "the revolutionary."  After a painful shock, it turns Thecla's body against her.  She tells Severian that she cannot stop her own fingers from clawing at her eyelids, and he tells her she will eventually tear her own eyelids from her sockets.  That kind of grotesque ingenuity is characteristic of The Shadow of the Torturer, which is as imaginative at worldbuilding as any fantasy or science fiction novel I've ever read.  The citadel, with its innumerable towers and lost rooms, reminds me most of the castle in the Gormenghast novels.  But it's halfway through the book, when Severian begins his journey away from the Citadel, that Wolfe's imagination really launches into high gear.  Severian doesn't get far, not even out of the city: he gets challenged to a strange kind of duel in which the weapons are poisonous flowers.  Along the way, a woman appears mysteriously out of a lake where corpses are buried and becomes his companion.  Shit gets weird.  Wolfe never seems to stop worldbuilding; each new chapter brings some kind of strange new element to be accommodated into our understanding of the world.  Since Severian hasn't traveled much outside his tower, however, it allows us to experience these things for the first time with him also.

We intuit, eventually, that Severian's Earth ("Urth") is a far-future version of our own in which the sun has begun to die and the world seems to be expiring.  Attempts to bring back the older world have filled it with prehistoric animals--smilodons and ancient horses--but it's still dying.  In a gallery of paintings, he sees a picture of the moon landing:

The picture he was cleaning showed an armored figure standing in a desolate landscape.  It had no weapon, but held a staff bearing a strange, stiff banner.  The visor of this figure's helmet was entirely of gold, without eye slits or ventilation; in its polished surface the deathly desert could be seen in reflection, and nothing more.

Later on, however, deep in the city's botanic gardens (he's there to collect his deadly flower) he encounters a pair named Robert and Marie who clearly have come from our world, or our era, and who see him as a kind of demonic spirit that they've summoned by accident.  It's a weird moment that's barely explored, but it throws our understanding of Severian's Urth off balance: is it the future?  Or perhaps another dimension?  On top of all of that, Severian has a number of visions that may be real or may be signs of increasing mental instability.  The Shadow of the Torturer is a book that loves the worldbuilding impulse of fantasy fiction, but looks on what it's made with a suspicious eye.

The novel ends with Severian at last, in the company of a flimflam doctor and an idiot giant, leaving the gates of the city.  It seems to end in the middle of Severian's journey, without resolution, but what kind of resolution can you expect?  The novel is gripping (despite what Brent felt), but it's also shaggy, and its weirdness and ambiguities make Severian's arc uncertain.  There is no quest, no sense that, Frodo-like, Severian must learn to find courage and defeat some evil.  It is entirely possible that Severian himself is the evil that must be vanquished.  But it's the novel's refusal to adhere to traditional fantasy narratives and archetypes that make it so appealing, and I had to exert a lot of willpower not to immediately crack open the next novel in the quartet.