'A master storyteller' Daily Mail

A goods train speeds through the Sapperton Tunnel, but disaster strikes before it can reach the other side as it collides with an unusual blockage on the tracks: seven sheep penned in place. Specially requested to investigate the carnage in Gloucestershire, Inspector Colbeck and Sergeant Leeming are confronted with a bizarre case unlike anything they've encountered before.

Stephen Rydall, board member of the Great Western Railway that manages the route, is convinced this tragedy is a personal attack on him and fears for the safety of his shepherd, missing since the incident. Rydall has many enemies: a churlish squire, a scheming principal and a local ruffian who always manages to evade the law. But, as Colbeck will soon discover, the man also has a closely guarded secret of his own...