'Anything you do in the past changes the future. The tiniest little actions have huge consequences. You might tread on an ant now and it might entirely prevent someone from being born in the future.'
 
The Discworld's most inept wizard has found himself on the Discworld's last continent, a completely separate creation.
 
It's hot. It's dry . . . very dry. There was this thing once called The Wet, which no one believes in. Practically everything that's not poisonous is venomous. But it's the best bloody place in the world, all right?
 
And in a few days, it will be except . . . Who is this hero striding across the red desert? Champion sheep shearer, horse rider, road warrior, beer drinker, bush ranger, and someone who'll even eat a Meat Pie Floater when he's sober? A man in a hat whose luggage follows him on little legs, who's about to change history by preventing a swagman stealing a jumbuck by a billabong?
 
Yes . . . all this place has between itself and wind-blown doom is Rincewind, the inept wizard who can't even spell wizard. Still . . . no worries, eh?