Everything you need to understand or teach Busman's Honeymoon by Dorothy L. Sayers.
In addition to the important presentation of the proper roles of husband and wife, the book illustrates Sayers's usual conservative picture of the class system. After the murder is solved, there is a substantial coda in which Lord Peter deals with his scruples about playing God in exposing the culprit by engaging the best lawyer possible for him and yet remaining haunted by the memory of his complicity in the death, no matter...