Death on a branch line - Andrew Martin

It's the sweltering summer of 1911, and one Friday evening a young aristocrat arrives into the custody of detective Jim Stringer, a man recently found guilty of murdering his father in the sleepy village of Adenwold. He warns Jim of another murder likely to happen in the same village - that of his brother, a reclusive intellectual. When Jim and his wife Lydia arrive at Adenwold they encounter a host of likely suspects and the intended victim, and suddenly Jim has one weekend in which to stop a murder and unravel a conspiracy of international dimensions...