Discworld is a world very similar to our own - if you overlook the fact that it is flat, and balanced on four elephants, which in turn are standing on the back of a giant turtle. The inhabitants of Discworld have their own version of Christmas, Hogswatch, and their own version of Santa, the Hogfather - who is pulled across the sky in a hog-drawn sleigh.

This year, however, something is amiss, when on the night before Hogswatch, Death (voiced by Richardson, Bleak House), who is responsible for escorting all beings to the afterlife, notices that the Hogfather's life-timer is lying broken on the floor of his castle. Could it be that Hogswatch will not happen this year?

With much of the fabric of reality dependent on the human power of belief, Death swaps his black shroud for a false beard and red coat to make sure that the children of Discworld remain blissfully unaware of the Hogfather's absence. With the help of his faithful servant Albert (Jason, A Touch of Frost, Only Fools and Horses) Death dutifully travels from house to house delivering gifts, leaving his granddaughter Susan (Michelle Dockery) to find the real Hogfather before belief in him, and subsequently Discworld is destroyed.