A Red Herring Without Mustard is by Alan Bradley. The third book in the marvelous Flavia de Luce series. Flavia allows a gypsy woman to park her caravan on Buckshaw land. When she returns to visit the woman Flavia finds her with her head bashed in; she rushes for the doctor and saves the woman's life - but on her way back to Buckshaw she finds a dead body in a fountain. This sets Flavia on the trail of yet another murderer. She must unravel a tangle of clues and dangerous secrets to solve this one. This is charming mystery series and if you have enjoyed the other two, this one will not disappoint.
Ratings: 9th grade - 9 out of 10 - V (violence) - AC (mature thematic content).