This story tells of brave Dickie Harding, the engaging little lame boy who lived at New Cross and spent a year with a tramp, besides having many other wonderful adventures. It tells, too, how Dickie nearly was made to be a burglar, of his great moon-flower, and the magic of its seeds, and how he slipped back in history five hundred years and became Master Richard Arden, who was not lame and poor, and how and why he came back again; of the Mouldiwarp, the Mouldierwarp, and the great Mouldiestwarp and what they did; of the buried treasure and how Dick and his friends found it, and so on to the end of the book.