Art teacher Walter Hartright takes a position as art master to a family in Cumberland but before he leaves London he has a chance meeting on the road to Hampstead Heath with a women dressed head to foot in white.
The woman is very agitated and Walter escorts her back to London. During the journey the woman gives Walter a shocking warning about the family he is going to work for. Once in Cumberland, Walter tries to find out who she is.
It was the last day of July. The long hot summer was drawing to a close; and we, the weary pilgrims of the London pavement, were beginning to think of the cloud-shadows on the corn-fields, and the autumn breezes on the sea-shore.
For my own poor part, the fading summer left me out of health, out of spirits, and, if the truth must be told, out of money as well. During the past year I had not managed my professional resources as carefully as usual; and my extravagance now limited me to the prospect of spending the autumn economically between my mother's cottage at Hampstead and my own chambers in town.
The evening, I remember, was still and cloudy; the London air was at its heaviest; the distant hum of the street-traffic was at its faintest; the small pulse of the life within me, and the great heart of the city around me, seemed to be sinking in unison, languidly and more languidly, with the sinking sun. I roused myself from the book which I was dreaming over rather than reading, and left my chambers to meet the cool night air in the suburbs. It was one of the two evenings in every week which I was accustomed to spend with my mother and my sister. So I turned my steps northward in the direction of Hampstead.
Events which I have yet to relate make it necessary to mention in this place that my father had been dead some years at the period of which I am now writing; and that my sister Sarah and I were the sole survivors of a family of five children. My father was a drawing-master before me. His exertions had made him highly successful in his profession; and his affectionate anxiety to provide for the future of those who were dependent on his labours had impelled him, from the time of his marriage, to devote to the insuring of his life a much larger portion of his income than most men consider it necessary to set aside for that purpose. Thanks to his admirable prudence and self-denial my mother and sister were left, after his death, as independent of the world as they had been during his lifetime. I succeeded to his connection, and had every reason to feel grateful for the prospect that awaited me at my starting in life.