Even a below average Christie is a solid outing.  While the opening of this book is all that you could want from the opening of a Christie book - mysterious, funny, tangled - as it progresses and the characters circle around and around each other, going from one explanation to another for the crimes, waiting on Miss Marple to sort things out, it becomes a bit of a grind.  Much of the humor and even tension comes from the mysterious and wholly improper dead body in contrast to the staid owners of the library, yet they disappear from the story almost immediately and don't return until the ending. This leaves us pinballing across the English countryside when we'd rather be having tea with Marple.