Cutter leads a band of insurrectionists from the Caucus, looking for the golem creator Judah. They fight a series of battles as they travel across a war-torn landscape, seeking the semi-mythical Iron Council, a group of railway workers who rebelled and escaped into the wilderness. Meanwhile Ori is involved with the shifting revolutionary factions in New Crobuzon. He joins one of the more violent groups, which eventually launches a plot to assassinate the Mayor.
Much of the "colour" of Iron Council comes from politics, with allusions to historical groups and events, most obviously to various socialist and anarchist movements and to the Paris Commune. It attempts to harness the pathos and power of revolutionary myth and history, but the result is mostly poor pastiche, nowhere approaching the drama of real history. The historical links are weak, often mismatched with the peculiar features of New Crobuzon, and unable to carry the sentiment Mieville tries to invest them with. And there's not enough background for anyone to actually care about the New Crobuzon revolution in its own right: Iron Council has neither actual political philosophy nor social detail nor real people.
Another annoying feature of Iron Council is that everything is subservient to the special effects of the moment. At one point, for example, we read:
"With a thumb of chalk, Spiral Jacobs drew the shape that had given him his name, whispering while he did, and it was of astonishing perfection, a mathematical symbol. And then there were smaller coils coming from its outer skin, and Jacobs ran his hand over it and walked on.
It began to rain as Ori reached the mark Jacobs had made. It did not smear."But though Ori and Jacobs continue to roam the city, the rain never features again — it's just a completely ad hoc device to highlight the mysteriousness of the spiral symbols. This is a trivial example, but this kind of thing recurs at different levels throughout Iron Council: strange wondrous monsters are invented, new magics deployed, characters introduced and then disposed of, new words coined — all to help enhance a single encounter, battle, scene, or piece of dialogue.
Mieville's characterisation is weak. The three central characters manage to get less and less interesting as time goes by, to the point where the deaths of two of them are of no moment. The plot and Mieville's dazzling invention hold Iron Council together and kept me reading to the end, but the overall effect is, apart from a few novel ideas, unmemorable and unlikely to bear rereading. It was no doubt unwise of me to expect more, but the fuss about Mieville and the recommendations of friends had raised my hopes.
Note: I haven't read Mieville's earlier books set in the same world — Perdido Street Station and The Scar — but Iron Council is entirely self-contained.