Julia Walker's review of this book is spot on and I totally endorse everything she has to say. I just want to add a couple of things.
1. Because the Crombie series, like Donna Leon's equally brilliant Brunetti series, is so character driven, I strongly recommend reading the books in chronological order. Then, by the time you get to this one, the 13th in the series, your involvement with Gemma, Duncan, their families, friends, colleagues and how their personal histories have evolved will be firmly in place, greatly adding to the many pleasures you'll find here. Here's the list, in order, updated December, 2014: "A Share in Death," "All Shall Be Well," "Leave the Grave Green," "Mourn Not Your Dead," "Dreaming of the Bones," "Kissed a Sad Goodbye," "A Finer End," "And Justice There Is None," "Now May You Weep," "In a Dark House," "Water Like a Stone," "Where Memories Lie," "Necessary as Blood," "No Mark Upon Her," "The Sound of Broken Glass," "To Dwell in Darkness."
2. This second comment is a bit off topic and relates to the atmospheric chapter header quotes that Walker mentions. Several are from Dennis Severs's book about his Spitalfields house at 18 Fogate Street. During my first trip to London in 1982 I spent an evening at one of Severs's otherworldly candlelight tours of his house and it remains one of my most memorable travel experiences; "Necessary as Blood" brought it all back for me. Any fans of this book enchanted with Crombie's portraits of today's East End and thinking of including it on an upcoming London visit should check out dennissevershouse online. Severs is no longer with us, but his house and its magical time capsule tours continue on Monday evenings, advance bookings required. For present day atmosphere, I recommend the marvelous 2007 indie movie "Brick Lane."