... is "A Small Death in Lisbon" by Robert Wilson. Actually, it's not the worst -- that distinction goes to Harlen Coben's dreadful "Promise Me" -- I just liked the best-worst symmetry of this and the preceding post.
Still, I didn't much like this book. While I admire the author's ambition and research, this is one of those yarns where meticulous geographic detail actually undermines the story.
The book is two intersecting tales about a modern-day sex murder and SS operations in Portugal during World War II, and it was deemed worthy of the Golden Dagger award. Which goes to show that I am not the best judge of these things. Two things put me off: the relentless recitation of Portuguese landmarks and street names, and the lack of a compelling protagonist in the Nazi-era portion of the tale. Since that part accounts for at least half the book, it's a serious shortcoming.
To paraphrase the old saying: I don't know much about writing, but I know what I like. What I don't like is a good yarn buried under an avalanche of minutiae.