Sorry to be violating blog etiquette, but this isn't a book. It's a game. But, it's a game about books, so hopefully that counts.
This game is along the lines of Balderdash or Wise and Otherwise (which our family is more familiar with). My sister-in-law brought it to our recent Christmas gathering. The idea behind the game is that one person (or team, which is how we played it) picks a card and reads the title of a book and a summary of the plot. The other people write down a possible opening line to the book. The person who read the card writes down the actual opening line (which is printed on the card). Then, that same person reads all of the lines. Everyone gets to vote for which line they think is the correct line. You get points for correctly guessing the opening line, or if someone votes for your line.
This is a fun game, but it was definitely more challenging than Wise and Otherwise, which we've done at previous family gatherings. In Wise and Otherwise, the object is to correctly pick out the correct conclusion to an old proverb. I hadn't realized how much harder it would be concoct an entire line than to simply complete a proverb.
The game is recommended for ages 12 and up. Parents might want to use discretion even then. Some of the first lines and plot summaries (I'm especially thinking in the romance category) might not be suitable for younger teenagers.