The group that selected this is a group that reads books that have to do with aging. Now quite a few of the characters were identified as retirement age. However, in only one segment was age a factor in the novel. Behaviors could have been most any age.

Two things were especially interesting: The narration shifted perspectives, often with a moment linking up two tellings of a similar moment. In spite of all that shifting, the perpetrator was not obvious.
And secondly, there was a lot more plot going on than mere "whodunnit."

One weakness: the theme/message/moral was hammered too heavily.

It is number 7 in a sequence of "Chief Inspector Gamache" mysteries. It stood alone. There may have been references to prior novels that would be fun for those who knew them, but I never felt left out. There was enough detail. I would read another in this series.

October 2016: And now I am reading the series from start to finish and have arrived at #7. I am rereading it to see the references to prior books as well as to refresh my memory. While it read okay alone (3 stars that reading), it is much richer after having read 1-6. Not only do I know the characters better from the previous books, but I also see some foreshadowing of events to come. I don't remember so much of the foreshadowing in #1-6. Is it a new thing, or have I just become aware? The foreshadowings are not the cliff hangers of soap operas, just loose ends.

On second reading, I did not feel the overpowering of the moral as much as I must have to make the comment the first time.