So Pretty a Problem by Francis Duncan
So Pretty a Problem is the third of the Mordecai Tremaine books. Mordeaci, our amateur sleuth, is a retired tobacconist with a fondness for romance literature. He's mild-mannered but a shrewd observer of people. Tremaine has accompanied his good friend Scotland Yard Inspector Jonathan Boyce to Cornwall for a relaxing holiday, with nothing on the agenda but lazing around and soaking up the summer sun. So, of course, Tremaine gets caught up in the murder of a local celebrity, painter Adreian Carthallo. Tremaine had met the artist and his wife, Helen, several months earlier in London and had continued his acquaintance with them in Cornwall, where their vacation home was.
I really liked how So Pretty a Problem was structured. First we jump right into the mystery. Adreian is dead and his wife admits to killing him - although accidentally. Of course, her story has holes galore and the local inspector isn't buying it. Happily, Mordecai is on the spot...