I was eleven. I was spending my customary winter weeks in bed. (My health improved, but I was twenty-five before I felt normal without a partial hibernation.) I had read the first volume of a wonderful adventure. My mother came into the room with new library books—that magical yet somehow threatening apparition—after the long hours alone (for years my favourite story of all time was Ray Bradbury's ‘The Emissary’). I saw the dingy olive grey spine of a tall, quarto volume. I can still feel the crushing disappointment: she's brought the same book back again. My God, no. She hadn't. It was Volume Two, The Two Towers. Take me away. Carry me away. Leave the meat behind.

In my devouring need for more of the stuff that made me high, I didn't notice I was rushing towards destruction. Other dramas close in media res, with a wedding or a funeral. The modern novel may drift off in inconclusion. Once the vital tension is broken a Fantasy series can amble away into soap-opera, as happens in countless Tolkien imitations. A trilogy is a world. This is true of any fiction, not only the overtly fantastic. At the end of the third volume, the world ends. It must.