Elizabeth Kostova's The Swan Thieves
Kostova's second novel has been getting mostly negative or middling reviews, but I haven't read The Historian in years and don't remember anything about it, so I didn't have super-high expectations or anything like that. And still, I just can't get into it. I gave it a fair shot--made it to page 100--but I find the main narrator (a psychiatrist treating an artist who attacked a painting in a museum but the artist won't speak and the doctor is trying to investigate his life or whatever, only it's on page 100 and hardly anything has even happened yet) fairly insufferable, the writing awkward and/or overly verbose, and the slow drawn-out plot to be somewhat annoying. If this was a 200 or 300 page book, I'd have plugged ahead to see if my guesses as to the ending were right, but it's over 560 pages, so screw it.