This is another great Tony recommendation. It has been a perfect audiobook in that the pace is slow and is repetitive enough so you won't miss any key points and interesting enough to keep you happy to take a walk so you can listen to it.
It is a nicely complex police procedural set in the province of Québec. References are made to events that precede it in the Chief Inspector Armand Gamache series, but of course it stands on its own. The Chief Inspector is based in Montreal, but lots of the action occurs in a small village which was the scene of a previous murder investigation. The characters in the town are wonderfully drawn.
Perhaps the best of the characters is the famous crazy old poet Ruth who has developed a waddle like her pet duck Rosa who, in turn, walks with a limp like Ruth. When Armand encounters Ruth and Rosa one morning while he is walking his dog Henri, she says, "I'm glad you keep the dumb beast on a leash. He's a menace." When Gamache retorts, "Henri is not a dumb beast, Madame," she snaps, "I know that. I was talking to Henri." When a group of villagers is gathered in the bistro or the bookstore, Rosa is prone to comment "Fack. Fack. Fack." Sometimes people aren't sure whether it's Ruth or Rosa who says it.
This is not the usual cast in a police procedural; the Chief Inspector is not an overweight, heavy-drinking recently-divorced man coping with equally problematic underlings. The evildoers have a larger field of operations and have a long-term plan that our hero must counter. Along with the menace and the murders, the author gives us a bit of humor in Ruth, a feel for the appealing village at Christmastime, cups of hot chocolate and delicious meals. In fact I was moved to search online for a good chicken with rosemary dish that I plan to make before long.
One strand of the story is the murder of an elderly woman whose fictional life was based very loosely on the actual Dionne quintuplets. Born during the Depression, they were the first known quintuplets to survive infancy. They were made wards of the state and Québec profited by making them a tourist attraction. You can read more about them at this Wikipedia site.
The title is from a Leonard Cohen quote: "There's a crack in everything. That's how the light gets in."
Louise Penny, How the Light Gets In, Minotaur Books, 2013, 416 pages (I listened to the audiobook). Available at the UVa and public libraries, and Amazon.