The film's tagline is: "A story of reality, fantasy and the bits in the middle". The series closely follows the plot of the novel, which, like many of Pratchett's novels, introduces an element of modern society into the magical and vaguely late medieval / early modern world of the Disc - in this case rock and roll music and stardom - with nearly disastrous consequences. It also introduces Susan Sto Helit, daughter of Mort and Ysabell and granddaughter of Death.