“Oh, I don't know, Mma. Five thirty, maybe.”

“Five thirty? Well, what do people do at five o'clock, Mma? They go home, don't they?”

This brought a fresh wail from Mma Makutsi. “He was taking her back home with him! Oh, Mma Ramotswe, that is what they were doing. They were going back to his house for immoral conversations.”

Mma Ramotswe made a dismissive sound. “Nonsense, Mma. You have no evidence that anybody was thinking about immoral conversations, whatever those may be. What if Phuti was simply giving her a ride home—to her home—because she had stayed late in the store? What if that is all that he was doing? In fact, the more I think about it, the more I think that it is the most likely explanation. Don't you?”

Mma Makutsi did not, but after a few minutes of further comforting, she appeared to pull herself together. “I must get on with my work, Mma Ramotswe,” she said. “It is no good thinking about these things when I am trying to work. There will be time to think about them later.”

“You should talk about it,” said Mma Ramotswe. “It is best to discuss these things, don't you think?”

Again, Mma Makutsi did not, and Mma Ramotswe decided that there was nothing further that she could do just then. It was time to go in search of Big Man Tafa, which she did, driving in her new, medium-sized blue van, which felt so alien, so wrong in every way.

Just as she was parking the van under a tree at the end of the street—a meandering, unpaved road of middle-range houses on the western edge of Gaborone—a small boy appeared. He was wearing a tiny pair of khaki trousers and a tee shirt several sizes too large for his spindly torso, had dust on his knees and a large sticking plaster across the bridge of his nose. And like all small boys who appear out of nowhere when one is looking for something, this one, she thought, would be bound to know in which of these houses lived Big Man Tafa. Small boys knew such things; they were familiar with the car number plates of every driver in the area; they knew the name of every dog associated with every house, and the vices of every such dog; they knew the best place to find flying ants when the rains caused the termites to crawl up from their subterranean burrows and rise up into the sky, unless a small boy snatched them first, tore off their fluttering wings, and popped them, delicious morsels, into his mouth; they knew which trees harboured birds' nests and which did not; and which of the area's residents would pay you four pula to wash and polish the car.

The Principles of Private Detection contained no advice on the seeking of information from small boys, but Mma Ramotswe had often thought that it should. Perhaps she could write to Clovis Andersen one day and tell him of the things that were not in the book but that might appear in a future edition. But where was he, this Clovis Andersen, who knew so much about private detection? Somewhere in America, she imagined, because he sometimes mentioned famous cases in American cities that sounded so exotic to her ears that she wondered whether they really could exist. Where was this place called Muncie, Indiana? Or Ogden, Utah? Or, most intriguing of all, this town called Mobile, Alabama? Did that town move from place to place, as the name suggested? What happened there? Would they have heard of red bush tea, she wondered. Would they have heard of Gaborone?