Terry Pratchett's Truckers (1988) is possibly my least favourite Pratchett book so far. The premise is that Nomes (4 inches tall, according to Wikipedia - the book itself only made it very clear they were quite small) living unseen among humans in our current world. They move immensely faster than humans - although they're also commensurately shorter-lived. Masklin is the hunter for a group of Nomes that used to be much larger. He comes up with the idea of climbing onto a human truck to find a new place to live, and so they end up at Arnold Brothers department store. The store is already occupied by thousands of Nomes: the welcome they receive is mixed. But Masklin finds even the department store Nomes looking to him to guide them when it's discovered that Arnold Brothers is closing and will be demolished.
The plot, of course, has never been the point of Pratchett's books. The point is the humour, and for me it fell totally flat in this book. Huge swaths of it are based on the Nomes misinterpreting human English, such as "Road Works Ahead" is determined by them to mean that the road functions well ahead. He was creative in the extent of his misinterpretations, but I found it remarkably unfunny. I don't expect I'll read the two sequels.