Hogfather

The Discworld is very much like our own - if our own were to consist of a flat planet balanced on the back of four elephants which stand on the back of a giant turtle, that is . . .
Oh, there has to be something in the stocking that makes a noise, said Death, Otherwise what is 4:30 A.M. for?
Superstition makes things work in the Discworld and undermining it can have Consequences. It's just not right to find Death creeping down chimneys and trying to say Ho Ho Ho . . .
It's the last night of the year, the time is turning, and if Susan, Gothic governess and Death's granddaughter (sort of), doesn't sort everything out by morning, there won't be a morning. Ever again . . .
The Discworld novels can be read in any order but Hogfather is the fourth book in the Death series; a festive feast of darkness (but with jolly robots and tinsel too).