Mma Ramotswe was fortunate in having an untroubled con-science, and therefore generally enjoyed undisturbed sleep. It was her habit to take to her bed after a final cup of red bush tea at around ten o'clock at night. Mr. J.L.B. Matekoni, her husband and by common consent the finest mechanic in all Botswana, would often retire before her, particularly if he had had a tiring day at work. Mechanics in general sleep well, as do many others whose day is taken up with physically demanding labour. So by the time that Mma Ramotswe went to bed, he might already be lost to this world, his breathing deep and regular, his eyes firmly closed to the bedside light that he would leave for his wife to extinguish.

She would not take long to go to sleep, drifting off to thoughts of what had happened that day; to images of herself drinking tea in the office or driving her van on an errand; to the picture of Mma Makutsi sitting upright at her desk, her large glasses catching the light as she held forth on some issue or other. Or to some memory of a long time ago, of her father walking down a dusty road, holding her hand and explaining to her about the ways of cattle--a subject that he knew so well. When a wise man dies, there is so much history that is lost: that is what they said, and Mma Ramotswe knew it to be true. Her own father, the late Obed Ramotswe, had taken so much with him, but had also left much behind, so many memories and sayings and observations, that she, his daughter, could now call up and cherish as she waited for the soft arms of sleep to embrace her.

Mma Ramotswe did not remember her dreams for very long once she had woken up. Occasionally, though, an egregiously vivid dream might make such an impression that it lodged in her memory, and that is what happened that morning. It was not in any way a bad dream; nor was it a particularly good dream, the sort of dream that makes one feel as if one has been vouchsafed some great mystical insight; it was, rather, one of those dreams that seems to be a clear warning that something special is about to happen. If a dream involves lottery tickets and numbers, then its meaning is clear enough. This dream was not like that, and yet it left Mma Ramotswe feeling that she had somehow been given advance notice of something out of the ordinary, something important.

In this dream she was walking along a path in the stretch of bush immediately behind Tlokweng Road Speedy Motors, the building that the No. 1 Ladies' Detective Agency shared with Mr. J.L.B. Matekoni's garage. She was not sure where she was going, but this did not seem to matter as Mma Ramotswe felt happy just to be walking along it with no great sense of having to reach a destination. And why should one not walk along a path, particularly a comfortable path, without any idea of getting anywhere?

She turned a corner and found herself faced with a large acacia tree, its foliage extending out like the canopy of a commodious umbrella. To dream of trees is to . . . to long for trees, and finding herself under the shade of this tree would have been enough to make the dream a satisfactory one. But there was more to it. Underneath the tree, standing in such a position that the mottled shade of the leaves all but obscured his face, was a tall, well-built man. He now stepped forward, held out a hand and said, "I have come at last, Mma Ramotswe."

And that was the point at which Mma Ramotswe awoke. The encounter with this stranger had not been threatening in any way; there had been nothing in his demeanour that was suggestive of hostility, and she had not felt in the slightest bit anxious. As for what he said, she had simply thought, even if she had not had...