The fourth book in Robinson's Inspector Banks series finds DCI Banks investigating the discovery of a decomposing, maggot-ridden corpse near a little village in the Yorkshire countryside. A possible connection with past events comes to light - an unsolved murder and the simultaneous disappearance of a local woman 5 years ago.
On the trail of the killer, Banks finds himself frustrated by the reticence of the local villagers, and it is clear that they know much more than they are letting on. When all the evidence points towards a Canadian connection, Banks heads to Toronto, where he makes a number of startling discoveries. Banks returns to Yorkshire with the mystery mostly pieced together. Unfortunately, the novel ends rather unexpectedly and almost anti-climatically, with little sense of closure.
The novel features an unnecessarily large cast of mostly one-dimensional characters, at the expense of already established characters. We do see more of Banks' superior, Superintendent Gristhorpe, and the interaction between them is fascinating. Unfortunately, Banks' family is relegated to the background, and their rare appearances serve only as a reminder that Banks has a family, rather than showing any meaningful interaction.
What frustrated me more were the 80-odd pages that Robinson devotes to Banks' trip to Toronto. A Torontonian myself (as is Robinson), I typically enjoy books that are set in Toronto - in this case, unfortunately, it turned out to be a major turn off. Robinson goes into almost excruciating detail describing the highlights of the city - it almost seems that the only reason Banks goes to Toronto is to give Robinson a chance to wax poetical about the city!
Finally, after tolerating a slew of in-jokes and stereotypical "Canadian-isms", I was practically eyeing the book with distaste. I was greatly relieved when Banks returns to his native England ("the old country" as Robinson puts it countless times).
All in all, The Hanging Valley falls short of expectations. As part of the series, it is an interesting book to read. I'd recommend it only to those who are willing to read anything starring DCI Banks (or those who want a detailed description of Toronto!).