Drawing conclusions - Donna Leon

Twenty years ago Venetian Commissario Guido Brunetti and his
creator, Donna Leon, first introduced readers to the delights-and
dangers-of Venice. Now they have millions of devoted fans. In
Drawing Conclusions, a young woman arrives home and senses that
all is not right in the apartment below. When she investigates, she
finds her neighbor lying lifeless on the floor. The autopsy shows that
the widow's death was due to a heart attack, but Brunetti is convinced
that things are not as straightforward as they seem. With her signature
combination of humanity, nuanced detail, and psychological insight,
Leon's twentieth Brunetti mystery reaffirms her place in the pantheon
of crime fiction.