When their father is taken away under mysterious circumstances, Roberta, Peter, and Phyllis and their mother must leave their house in London to live in a small cottage in the country. Their house, called "The Three Chimneys" stands not far from a railway track, where the three have a number of adventures. They are befriended by the Station Master and Perks the Porter, and run each day down to the railway track to wave at the passing train for London, sending their love to father. Unknown to them, a kindly "Old Gentleman" who waves to them every day from the train helps them to solve the mystery of their father's disappearance. This classic tale by Edith Nesbit has the original illustrations by C. E. Brock.