The Beautiful Mystery is the eighth episode in the Armand Gamache/Three Pines series, set in the Eastern Townships region of rural Quebec, southeast of Montreal and just north of Vermont. Armand Gamache works for the Surete du Quebec, the provincial police force based in Montreal, and he often investigates crimes that occur in or around the remote village of Three Pines.

This time, though, the main storyline takes place at Saint-Gilbert-Entre-les-Loups, a stone-walled monastery perched in a remote portion of the rural Quebec wilderness. Three Pines may be a small, closed community, but it's nothing compared to a monastery that can only be reached first by plane, and then by boat. It serves as home to 24 monks who have taken a vow of silence. It is a place of Gregorian chants, chocolate-covered blueberries and, usually, peace. But when long-time choirmaster Brother Mathieu is found dead in the abbot's private garden, Chief Inspector Gamache and Inspector Jean-Guy Beauvoir are called to the scene. They sequester themselves here in order to investigate and to solve the murder. Abbot Dom Philippe has temporarily lifted the vow of silence. But will the monks be willing to tell the officials what they know? Will they explain why there is a dividing line between them? What suppressed evil has risen to the surface here?

Just as the duo seems to be making some headway in solving the crime, their attentions are diverted by a sudden administrative issue. Effects of the Arnot case and the factory raid -- Surete situations from the past, which are detailed in previous books -- still linger among members of the force and still have ramifications on present-day operations. The provincial police have long memories. (Readers must remember too, in order to fully grasp the significance of what happens here.) A certain strife in the Surete has followed them to the monastery. It adds another dimension to the burdens already on Armand and Jean-Guy. Can they recover from it?

Away from the investigation, and on the personal front: Armand and Reine-Marie's daughter Annie has separated from her husband David. She and recently-divorced Jean-Guy are starting to see one another, and they haven't yet told her parents. This development should be fun to watch.

Opening a Louise Penny novel is like starting to dig in to a full course meal, consisting of many elements: only some of which you are able to see at first. And just when you think you've figured it all out and have digested it all, the chef/author/creator pushes another small, crucial dish into your line of sight. And this one changes the way you consider all that has come before. Penny makes this happen in the last few pages of every book, every time. Wow! This technique and her wonderful way of storytelling are what keep us reading, page after page, book after book.

The Beautiful Mystery may be among the most imaginative books in this series, since readers have to imagine the monastery, its location and its configuration. (Sorry, no Three Pines residents appear in this one.) Penny asks us to think when we read. She challenges us. And this challenge is well worth taking, again and again.