The Balrog, The Book, and the Bridge of Khazad-Dûm
I don’t know if Tolkien was a believer in the Rule of Three: the idea that jokes are funnier, instructions more memorable, or stories more evocative if they come in threes. The idea popped up when I finished “The Bridge of Khazad-Dûm.” It’s the third chapter in a row that throws an unexpected hurdle at the Fellowship, it’s the third chapter in a row that ends on a curt, brusque note of defeat. Start to look too hard you can start to see it everywhere. Three battles of escalating difficulty, three final drum rolls as the Company spills out into the Dimrill Dale, key phrases repeated three times.
This sort of thing easily becomes silly, of course: you can also find patterns of two, four, six, or eight. But there’s a reason I was looking for patterns to explain “The Bridge of Khazad-Dûm”: there had to be something to explain why it’s so good. It’s a masterpiece of structural suspense and a vivid, near-perfect chapter.