A Trout in the Milk

It is just before Christmas of 1937.  Circumstantial evidence is not supposed to be admissible in court, so when Roger Aston is arraigned for a murder he did not commit, he appeals to his cousin, Miss Joanna Birtley-Meriden (Doodle to her friends), for help.  She sets to work to find the proof they need to clear his name before he is hanged.  Descending with cautious but increasing relish from her superior position in society she becomes unofficial driver to the new Inspector from Scotland Yard, who has few social graces and less experience--and the less said about her reasons for involving him, of all men, in Roger's affairs, the better.  But if Roger didn't kill the kindly, harmless old woman, who did--and why?  Joanna has to cope with her hunting-mad father and fend off her just plain mad mother while enlisting the assistance of a few faithful friends and servants.  Roger's sweetheart, Rowena, is less helpful than she should be, but the true culprit is unmasked all the same.