This month my book club discussed The Golden Compass, the first book in Philip Pullman's His Dark Materials trilogy.
The Golden Compass is a young adult book that can definitely appeal to adults as well. Everyone in my book club enjoyed the book, even those you generally shy away from fantasy and young adult books.
I think one of the things that sets The Golden Compass apart is how Pullman is able to present this wonderfully complex world, one that is very much not our own, but that bears enough resemblance that things feel familiar. One of Pullman's best inventions is the daemon, a physical manifestation of each character's soul in animal form (when the characters are children their daemons are continually changing form, at puberty the daemons set for life).
The Golden Compass includes a wonderful array of characters -- including witches, child-stealing "Gobblers", armored bears, absentee parents, evil scientists, and ship-going gypsies -- and an interesting plot.
The novel is a page turner and readers quickly become invested in protagonist Lyra and her quest. Once I read The Golden Compass, I had to continue the series so I also read The Subtle Knife (definitely the second book in a trilogy, somewhat disappointing) and The Amber Spyglass (a good conclusion to the series, satisfying).
If you haven't read these books, I'd encourage you to pick them up. They're not perfect, but they are good reading. I don't want to say too much more for fear of giving too much away (I had to zip my lips a bit at the book club meeting precisely because of that). A few more descriptive words should suffice: unique, subversive, enchanting...