Stop me if you've heard this one: at the end of history, the entire human race is resurrected on an alien world, to live all together in immortal bodies. (SF writers take this premise as an excuse to throw lots of entertaining historical figures into the story. ...Yet another demonstration that Dante was an SF writer.)
Anyhow, this is the same trope as Riverworld and vulgar Christian eschatology, but it embraces the space-time-opera gonzosity of the Faction Paradox setting. The City of the Saved (parse that term as Calvinism or a flash drive, your choice) is not planet-sized; it's galaxy-sized. It's inhabited by every human being in recorded history. That is: every human being in the history of homo sapiens -- tens of thousands of years of prehistorical rock-banging, thousands of years of technological development, and then millions of years of interstellar civilization. Civilizations. Colonies, empires, republics. All of them. Prehumans, posthumans, part-humans, cyber-humans, mod-humans, uploaded humans... a population measured in septillions.
(Or, perhaps, trillions of times greater than that. Whenever a time-travelling Warship alters history, the City seems to contain all the human lives from both alternate timelines. And with the Time War raging, histories are being altered and re-altered all the... well... all the time. As it were.)
One fears that the storyline might be unable to stand up to this fantastical backdrop. One would, regrettably, be right.
It's a murder mystery. Among N-illions of immortal beings, one politician gets stabbed (this is impossible) and bleeds (impossibly) (and messily) to death all over his office. Why? How? Has the War finally reached the City? (It's tried before.) Will death's foothold in Heaven prove contagious? (Hint: yes.) Is it a good murder mystery? Not really.
We get a bunch of narrative viewpoints and a bunch of narrative threads; I guess it's trying to pull same trick as This Town.... But it fails. The characters aren't interesting and threads don't stick together. Worse sin than either: Of the City... is fanfic in the way that This Town... isn't; it relies on canon. The story (and solution) depends on knowing the history of Compassion, Timeship and mother of Timeships, in the Doctor Who novels that Faction Paradox originally split from. Oh, the book tries to introduce the necessary backstory -- it's packed with sidebars and footnotes -- but it's both insufficient and too much information. It doesn't work.
So, whither Faction Paradox? I've read three volumes, which score two idea-packed failures and one success despite itself. I have three more volumes on the shelf, plus a collection of short stories. I expect the success ratio to remain low. And yet I'm still interested. Faction Paradox is an inchoate narrative fog which may contain nothing but will-o-wisp and ambition. How can I say no?
(Added afterwards: I have now looked up some of the drama from fifteen-odd years ago -- when the Who novels in question were being written. I am adding this footnote to say: don't. I shouldn't have looked. Maybe that should taint this whole review, but you know, I'm just gonna go back to reading the books.)