Darkside, By Belinda Bauer

Belinda Bauer's Blacklands caused the hearts of hardened reviewers to flip a beat. Was that extraordinary insight in to a battle of wits between a murderer and a young boy just a one-off sensation, or was this newcomer to the crime lists capable of another book on the same level? Happily for the genre, Darkside shows she can do it again. Bauer takes the same setting, a sleepy Somerset town, with the same people, but shifts the focus, so that the boy who was the principal character in the previous book plays a minor part and the narrative is seen mainly through the eyes of the local policeman, Jonas Holly, and his wife, Lucy, who suffers from MS.

To the villagers, Jonas is a trustworthy, familiar figure; to Superintendent Marvel, dispatched from Taunton to investigate a suspicious death, Jonas is a dumb country hick. Marvel is splendidly sardonic about the rural life, yet shocked beyond reason when his car hits an Exmoor pony and he is directly confronted with a dying creature. Hated by his juniors, he finds comfort only in Dubonnet-drinking sessions with an elderly alcoholic.

Jonas, meanwhile, is confronting his wife's increasing disability and his private fears. Their marriage is recounted with a clear-eyed refusal to sentimentalise the character of Lucy, who struggles valiantly for independence but is in no way a saint or martyr.

When a second body is discovered floating in an icy stream, Jonas's position in the village appears to change. Someone thinks that far from being a trusted protector, he is the killer, and anonymous letters shake this village bobby's confidence in himself and his relationships with the neighbours he has known all his life. Could he have saved the dead woman? As the "shepherd" of the village, he feels he has failed in his task. Things get scarier: the anonymous notes betray close knowledge of his movements, even inside his home. Has someone been watching his cottage, peering in to the most intimate details of his life? Yet he must do his duty: he is needed more than ever by the community.

Meanwhile, the police are theorising that because both victims were heavily dependent on their relatives, there may be an epidemic at work. Once the first murder had been committed, a taboo was broken: someone can ignore their conscience and set about disposing of those seen as "burdens". As if in confirmation, there is a mass killing at an old folks' home and even Marvel's flippancy cracks at this new horror, "not a killing ... a cull". And if the weak are being targeted, then the crippled Lucy will be in the killer's sights.

Tension mounts with extraordinary yet credible narrative twists. As in her previous book, Bauer takes astonishing risks but - like a brilliant ski-jumper - arcs down to the perfect landing.