With The City, Darren Shan seems to have filled a very particular niche. This is a dark series but well done, equal parts mystery and horror, casting a host of villains and really no traditional "pure and uncontaminated" heroes. While plenty of horror stories exist that deal with a nexus of pure evil, Shan's is unique for leaning toward the fantastical and somehow not becoming corny. It would seem overly misleading to call it a dark urban fantasy because it is quite dark --- much more than readers might expect from a novel traditionally placed in that genre.
Building on the story Shan has already meticulously laid out, CITY OF THE SNAKES jumps forward a few years, after the Cardinal Capac Raimi has become comfortable on his throne but is finding that power lacks some of its previous luster. To be clear, this isn't because Raimi has not yet discovered that happiness lies in cultivating his conscience; he doesn't have any human qualities. Beyond being a creature who isn't strictly human, he's an evil dictator who knows no other way to be. Raimi is simply disturbed because things aren't going quite as planned. New factions are arising that question his leadership. His own men have been attempting to assassinate him recently, hinting at a loss of control. He's been reincarnated so many times that he cannot count how many, and once he realizes something is quite wrong and begins seeing ghosts of long-dead people, he arranges for a temporary replacement while he uncovers the source of the problem.
Tasso Ford, an important character in previous volumes, is the one chosen to sit in as his replacement. Once Raimi disappears, Ford becomes the indefinite leader of The City. This is a job he doesn't want, but as Raimi has vanished, he's stuck. He seeks the help of an old ally, Al Jeery, the sharp-witted detective in Book Two. But the new Al is not the same person we all got to know in the last volume. It seems the City and its men have corrupted him, just as they have everyone else.
Al has become a ruined killer, taking on the likeness of his evil, ruthless father in a feeble attempt to obtain some twisted form of justice. Though the serial killer, Paucar Wami, was wiped out with the first Cardinal, Jeery has now taken his place --- truly --- wearing not only the mask of the serial killer but assuming the personality of a heartless man, killing over and over, for no other reason than his obsession with luring out a prized victim. He has sunk beneath where he thought he could, and his only care now is to kill the man who destroyed his life: Bill Casey, the father figure who is now assumed dead by all but Al.
Hiding behind makeup to disguise his new face, Al retreats into his previous persona and begins the investigation alone, alternating dual personalities of a killer and vaguely good man. While he searches for trails of Raimi, his only care remains in fulfilling the promise of receiving the hiding place of Bill Casey. But all trails have run cold, at least for a time, until the evil of The City breaks wide open into violence and outright guerilla warfare. Amid rival gang wars, the villacs make their appearance, making it clear they're back and never had lost power, having returned to reclaim their city and all the Ayuamarcans, past and present.
CITY OF THE SNAKES resolves the mysteries left unsolved in previous volumes while revealing a good deal about the psychology of the killer --- or the psychologies of multiple killers. One of the main themes here is that, even in this hellish place, there are always varying shades of good and evil. The Ayuamarcans are not human and so make particularly notorious criminals. Guerilla warfare takes up a good portion of this final installment and should captivate readers. And there will be many more who will be pleased to discover that not all scoundrels are past all hope of redemption.