Bibliophile at Another 52 books has an occasional series called Bad Book Covers. She has found a good subject today, featuring an apparently psychotic nun. Take a look at the good and bad points of the cover of "A Novena for Murder".
Another favourite blog of mine, Book of the Day, owned by Mapletree 7, also occasionally features bad or misleading book covers. Mapletree hasn’t featured one for a while, possibly because she is getting bogged down with those American novels, but here are a couple of examples: Can a cover trick a reader? and Who wrote it?