Last night, I finished Farthing by Jo Walton.

Farthing is an alternate history story, one of many involving WW2 and the Nazis. In this one, the peace mission Rudolf Hess was on was successful, and a peace was made between Germany and England, allowing Germany to tackle the USSR without interference and the US ends up under the leadership of the fascist sympathizer Charles Lindbergh, similar to Philip Roth's The Plot Against America.

But all that aside, Farthing is really a pretty straightforward mystery/police procedural where we get to explore the inner workings of a rich, upper class British family after a murder that may, or may not, have political motivations. It's well written and doesn't follow the obvious cliches of either of its genres.