Advance Readers Copy through Goodreads (yay). This is a lucent, complex, thoroughly satisfying mystery, a variant of the traditional closed room classic (you know: there were five people in the room and one is murdered and one of the others must have done it...but who?) in which the closed room is a hidden, remote monastery in Canada. So hidden is this monastery that even the Vatican doesn't quite know where they are.
Wonderfully vivid description, and poignant parallels between loyalty and order amongst cops and loyalty and order amongst monks. And woven through..the use of music as a way to the Divine. Can music be an avenue of prayer and realization? Or is it an addiction? Can men sworn to a closed life (as cops, as monks) truly love, and what does that mean?
And what drives a peaceful soul to murder?

I haven't read Louise Penny before, but I will be seeking her out now; this is beyond excellent. It's going on sale in late August this year (2012)...look for it!