“The sun rose slowly, as if it wasn't sure it was worth all the effort.”
― Terry Pratchett, The Light Fantastic
In two months the world is going to end, or else something bad is going to happen, unless the eight great spells are read at that time. The only problem is that one of those spells is in the head of Rincewind, the Disc's worst wizard, and he's far away, tumbling over the edge of the world.
These pieces of information are given rather early in the second novel of Terry Pratchett's Discworld series, and help to set the pace and plot for the rest of the book. If you look back at my review of the first Discworld novel, The Color of Magic, you'll see that my number one complaint of the previous book was that there wasn't really any overarching plot unifying the story. Right from the onset, The Light Fantastic does