“And they stayed there for some time,” said Mma Makutsi. “I think they were visiting the people who live there now, whoever they are.”

“That could be true,” said Mr J.L.B. Matekoni. “The people who live in my house will have friends, no doubt. Perhaps this lady with the Mercedes-Benz is a friend of those people.”

Mma Ramotswe agreed that this was a possibility. But the apprentices were always happy to gossip, and if they were mixing socially with Mr J.L.B. Matekoni’s tenants they might well have been expected to mention the fact, surely?

Mr J.L.B. Matekoni now shrugged. “It is Charlie’s affair,” he said. “If he is going round with this woman in his own time, then that is his business. I cannot stop those young men from having girlfriends. That is not my job. My job is to teach them to work on engines, and that is difficult enough. If I had to teach them about looking after themselves once they leave the garage, then …” He spread his hands in a gesture of hopelessness.

Mma Ramotswe glanced at Mma Makutsi, who asked, “Who is your tenant, Rra?”

“His name is Ofentse Makola,” he said. “I do not know much about him, but he has been paying his rent very regularly every month. He has never been late with it—not once.”

Mma Ramotswe caught Mma Makutsi’s eye, signalling to her that they should bring this discussion to an end. Mr J.L.B. Matekoni looked a little bit awkward, she thought, and it would be best not to press him at this stage. Besides, she wanted to find out who owned the silver Mercedes, and this would require his co-operation. If he thought that the two of them were up to something, then he might decline to help. So there should be no more talk of Charlie’s exploits for the time being.

After Mr J.L.B. Matekoni had returned to work, Mma Ramotswe busied herself with some telephone calls before she turned to Mma Makutsi and asked her directly what she thought they should do.

“Should we bother to find out anything about this woman?” she asked. “Is it really any of our business?”

Mma Makutsi looked thoughtful. “Charlie is a young man,” she said. “He is responsible for himself. We cannot tell him what to do.”

Mma Ramotswe agreed that this was true, but then, she asked, what should one do if, as an older person, one saw a younger person about to make a bad mistake, or do something wrong. Did one have the right to say anything? Or did one just have to stand by and let matters take their own course?

Mma Makutsi considered this for a moment. “If I was about to do something foolish—really foolish—would you tell me, Mma?”

“I would tell you,” said Mma Ramotswe. “I would tell you and hope that you would not do it.”

“So should we tell Charlie to be careful? Is that what we should do?”

Mma Ramotswe very much doubted whether Charlie would take advice when it came to the matter of a woman, but thought that perhaps they might try. “We could try talking to him about it,” she said. “But we don’t really have much to go on, do we? We don’t know anything about this woman, other than that she has a Mercedes-Benz. That is not enough to go on. You can’t warn somebody if you know only that. You can’t say: Have nothing to do with ladies who drive Mercedes-Benzes! You can’t say that, can you, Mma?”