Peter and Phyllis growing up in Victorian London. An unexpected event sees their father taken from them and causes the family to fall upon hard times. The children and their mother move to the countryside, where they make new friends and have many wonderful adventures on the railway.
When four brothers and sisters discover a Psammead, or sand-fairy, in the gravel pit near the country house where they are staying, they have no way of knowing all the adventures its wish-granting will bring them.