There were two places called Mokolodi. There was the small game reserve to the south of Gaborone, barely a mile off the Lobatse Road, and there was the farm with its large stone house, the original Mokolodi, where Mma Ramotswe’s friend Gwithie lived. They had all been one large farm in the past, until the land was given to the children of Botswana for a nature reserve. Mma Ramotswe knew the reserve well, and had some years previously helped them with an issue of superstitious staff being frightened by the presence of a ground hornbill. That bird! Now here was Mma Soleti being driven into a state of fear by a single feather. It was ridiculous, completely ridiculous, that otherwise sensible people should believe in things like that. Except that they did. People believed all sorts of things and were not easily persuaded that what they feared was really harmless. And the things they believed by day were often different from the things they believed at night. The shadows you saw on the ground at midday were just that: shadows caused by some very ordinary object that blocked out the sun. The shadows you saw by night, by contrast, could be the shapes of things with no name: things that moved silently and changed their form; things that could touch the skin with icy coldness; things that could draw the breath out of your body and leave you gasping for air. It was all very well saying that such things did not exist, but to the people who saw them and felt them they were as real as the ground beneath their feet.

The gates of Mokolodi were topped, as it happened, with an ornamental hornbill worked in iron. This was the ordinary hornbill, though – the cousin of the bird that spent much of its time grounded – and it did not have the same power to frighten. Perhaps, she thought, if you wanted gates to do the job of discouraging unwanted visitors, you might put the ground hornbill there.

She passed through the gates and drove up to the main house. Here she parked in the shadow of the house itself – a cool well of shade that would keep the cab of the van from feeling like an inferno when she returned to it. As she got out, her friend appeared from the side of the house, a gardening trowel in one hand and a basket of plant cuttings in another.

Gwithie put down the basket and walked over to the van to welcome Mma Ramotswe.

‘Mmapuso,’ said Mma Ramotswe as she got out of the car. ‘Dumela, Mmapuso.’ She used the name by which the other woman was generally known – Mmapuso, the mother of Puso. She too had a Puso, the same name as one of Mma Ramotswe’s foster children. Mmapuso had lost hers some time ago now, but the name remained.