Imagine a twilight graveyard and three men in the shadows. One of them is carrying the other over his shoulder, and this one seems to be tied up. The last man is leaning both hands on the top of his cane. Voices float through the purple air. "Congratulations, your grace."

"I suppose so."

"On the birth of your son, I meant."

"Oh…yes. Oh. Of course. Yes. Well…thank you."

"A healthy lad, I am given to understand."

"We'd have been just as happy with a daughter."

Ah-ha. And once more, a leg of the infamous Trousers of Time opens up, and we are hurtling through it, past spinning galaxies and strange clouds and through the multi-coloured fire at the heart of stars until-

Darkness. Chthonic darkness, that puts the impossible[1] watcher in mind of a black cat in a coal cellar at midnight. The kind of absolute darkness, in fact, that may be worn by Death as his robe. And then… a shifting of perspective, and the watcher sees that what they had originally thought was part of the inter-stellar vastness of space is the actually the ice-rimed, crater-pocked surface of a giant flipper, and this flipper is connected to a carapace, and on this carapace are four gigantic elephants, and on the backs of these four elephants-

This is the Discworld, world and mirror of worlds, one Universe amongst many. It coasts gently on the bubbled surf of Fantasy, sloshing across the rocky beach of Reality. Observe. At the very centre, there stands Cori Celesti, home of the most ragged and argumentative pantheon ever to be brought to life by belief. See the Circle Sea, forever draining away into space. See the Counterweight Continent, and dusty Fourecks, Lancre of witches, the Chalk and Klatch. Let the Sto Plains pass below the watcher towards the haze of smoke, smog, fumes and steam that denotes the position of city of cities, Ankh-Morpork. And now, zoom in…closer.

[1] At least, if they are not intangible, then their recent sojourn through space and time has left them confused, temporally unmoored and of a consistency that will be something akin to lumpy Bolognese once they thaw out.