Brunetti's inquiries around the nursing home issue seem to be going nowhere, but when Maria Testa is involved in an accident it seems someone is out to ensure her silence, and Brunetti has suspicions about the involvement of Opus Dei, an organization of super-pious believers.
With Maria Testa in hospital Brunetti arranges for a police guard, something Vice-Questore Patta is quick to order cancelled when he returns to the office. Fine, the officers involved continue the arrangement in their own time.
In the end there’s no obvious solution to the Maria Testa case, though the strands end up rather neatly tied together in a reasonably satisfactory ending (at least as far as Brunetti is concerned).
The reader’s reaction will, as suggested above, depend largely on their own stance on provocative religious and political issues. It’s totally obvious where Brunetti's wife stands on those issues, with her dislike and distrust of the Church verging on anticlerical militancy. Brunetti is slightly less militant, inclined towards compromise, but still quite firm in the dislike and distrust department, and if there’s anyone familiar with the series who’s surprised by Signorina Elettra’s attitude to ecclesiastical malfeasance I’d suggest they haven’t really been following the way her character has developed.
Quietly in Their Sleep comes across as a gripping mystery with emerging plot lines that add intrigue, but, given the subject matter and the social setting mileages may vary.