In the Welsh borders, isolated by heavy snow and flooding from the thaw, cut off from telephone access, a tragedy has occurred. Old Dr Robinson known to be a menace on the roads has met his end in a car crash, his big saloon thrown from the track down the steep hillside. But when the police arrive there is more to the tragedy than meets the eye: why was there a second body - an outsider to these parts - in the back of the vehicle? As the local inspectors dive into the muddy waters of this strange crime, Chief Inspector Julian Rivers and Inspector Lancing of Scotland Yard are called to investigate, with danger and deceit lying in wait among the lonely hills and authentically evoked landscapes.