A Most Efficient Murder by Anthony Slayton
The very private, bookish Earl of Unsworth hosts his first party in over a decade, but it goes awry when an unknown young woman is found murdered in the garden. When the police arrive, they quickly start asking questions of Lord Unsworth and his aristocratic family, which of course they don't appreciate. Mr. Quayle, Lord Unsworth's secretary, is asked to keep an eye on the investigation while also conducting an investigation of his own. Mr. Quayle's primary goal is to keep any scandal away from the family. Secondly, he does want to discover who the murderer is, regardless of his or her social position. He also knows the lead detective on the case - they served together in the war - which helps a little.
I have to admit to a fondness for mysteries set on old English estates and a cast of interesting characters. The Unsworth family is an interesting set of characters. They are each well aware of their...