A deft mix of police procedural and urban fantasy, Aaronovitch’s Rivers of London follows Peter Grant, police constable in central London and all round nice guy. After coming across a voluble witness to a murder (who himself is already dead), Grant is plunged into the magical and twisted underside of the city and apprenticed (in more ways than one) to England’s last wizard, Inspector Nightingale. Together they must attempt to hunt down a vengeful spirit that threatens to bring chaos to the city whilst avoiding the wrath of varying Chief Constables.

This book has such potential that it is hard to accept it as what it is; a light hearted, well-plotted, well-written adventure story. The problem lies in a lack of exposition; the titular ‘rivers’ are the god’s and goddesses of the Thames, a wonderful idea sorely lacking in any pursuance. A few brief historical allusions to the more obscure subterranean rivers are never expounded upon, so that the reader finds himself in the awkward position of wishing for just a little more. Yes, there are vampire nests in Purley and graves in Covent Garden and improbable names all round, central London wonderfully evoked as it rushes by, but so little is explained it is infuriating.

A long series is clearly in the offing and the author does not want to show all his cards just yet

The central plot is well carried off and certainly enjoyable, but so much more is dangled in front of the reader and then snatched away; the sequel is almost worth buying simply on the off chance the motivations and histories of certain characters are. The other area in which this novel falters slightly is in its attempt to cater to adult audiences. This essentially means a reasonable volume of gratuitous violence and some sheepish sexual references, all done with schoolboy awkwardness and lack of finesse. Aaronovitch seems unwilling to commit to full blown adult sex and violence, falling back to pre-watershed levels of innuendo (if not gore).

Rivers of London is a good read, enjoyable, and certainly better than much else out there. It is tightly plotted and welcoming, and it is only afterwards that you feel a sense of disappointment. A long series is clearly in the offing and the author does not want to show all his cards just yet, which leaves you wanting someone who had more cards to begin with. For adult ‘urban fantasy’ go and read King Rat or Kraken by China Miéville or American Gods by Neil Gaiman, titans who Aaronovitch cannot yet match. Rivers of London is entertaining and readable, with a good premise and reasonably sharp execution. What it lacks in depth it makes up for in pace, and there is always the hope that the world built here will be expanded on more fully in the first sequel, Moon over Soho.

Rivers of London is out now in paperback. Moon over Soho is out now in hardback.