Television shows and movies don't have a monopoly on "holy crap, what just happened" moments. Science fiction and fantasy books are full of twists and events that make you throw the book across the room... then run to retrieve it, so you can know what happens next. What's the most shocking scene you've ever read?
Please include a book cover, piece of fan art, or other representation for the book in question. And please mention the book's title, the author, and what the horrifying event was (with suitable vagueness, if it's a huge spoiler.) And if it's fan art, please link back to the artist's site. Thanks!
Top image: The Red Wedding in George R.R. Martin's A Storm of Swords is an obvious candidate. Of course, the above image is from the TV version, but long before HBO drove us crazy with Game of Thrones, Martin had already made book readers scream all over the world.