Wild Fire by Ann Cleeves
My rating: 4 of 5 stars
This can't be the last Shetland book?! Sigh. At least it's ending on a good note, with enough left open should the author revisit the series. As far as mystery goes, there are parts that were easy to predict (like whodunnit and why) but the characters are so well drawn that it didn't matter.
If you've watched the tv version, you may (like me) be surprised by Cassie being much younger in the books than on tv. That doesn't actually matter to the book in terms of plot, except where Duncan is concerned, but it's one more reminder of how things changed between the two.