River of Darkness  - Rennie Airth
Another bookswap book, this time the first in what I thought was a series but which may only be a trilogy?

It's the 1920's and England is still recovering from the aftermath of the War, with visible scars in the shape of missing sons and less obvious ones in terms of those who came home but left a part of themselves in the trenches. There's been a series of horrific murders, originally blamed on a robbery gone terribly wrong, but our protagonist Inspector Madden has seen those kind of wounds before, on the dead and injured of the battlefield.

Determined that this is the work of one man, a man obsessed with what happened during the War and now wielding a bayonet as his weapon of choice, Madden tries to understand what drives a man to do this kind of thing, while also getting involved with the local doctor who is equally intent on embracing life.

River of Darkness is an odd book, because it doesn't feel as though it's sure what it is - on the one hand, it's an attempt at a golden age crime novel but then there's the element of the psychopathic serial killer to deal with, since Sayers and co. don't really come across that sort of thing in such an explicit fashion. Perhaps it's this, not to mention the romantic sub-plot which seemed a bit like wish fulfillment, that left me ultimately somewhat unsatisfied and uncertain whether I'd continue with the next in the trilogy, The Blood-Dimmed Tide.