Mma Ramotswe did not answer; she had her own questions to ask, and they came tumbling out. “And why are you driving that car, Mma Potokwane? How was I to know it was you? I thought that I was being followed by some…some…” She faltered. Some Tsotsi? Kidnapper? Writer of anonymous letters?

Mma Potokwane let out a hoot of laughter. “Followed? Of course I was following you. I saw you just before you turned into Zebra Drive. I saw your van. I wanted to give you something that I’ve made for Mr. J.L.B. Matekoni. And this car—it belongs to one of the volunteers. They let me use it whenever I like.”

Mma Ramotswe forced a smile. “It was silly of me,” she said. “I just thought…You know, with my work, Mma, I sometimes get threats.”

Mma Potokwane frowned. “People threaten you, Mma Ramotswe? Why would anybody want to threaten you?”

It was difficult to explain, particularly standing there in the late afternoon heat. And Mma Ramotswe thought that Mma Potokwane had little idea of what was involved in running a detective agency. She knew everything there was to know about managing an orphan farm, about getting things for the children, about cajoling supporters into donating, about making do with whatever she could purloin, but she knew nothing about the world of a detective agency.

“Sometimes I have to look into the affairs of people who don’t want me to do so,” she explained. “People can get angry.”

Mma Potokwane shrugged. “We all get angry. I get angry with my husband from time to time, but I don’t follow him.” She laughed. “Perhaps wives should follow their husbands occasionally, though, just to see what they get up to. Perhaps it’s a good idea, Mma Ramotswe.”

The matron now reached over the back of her seat to retrieve a large tin from the back of the car. “This is for your husband, Mma. You can guess what it is.”

Mma Ramotswe could. And she knew too that the large, heavy fruit cake that the tin would contain would be more than a mere present: it would be a cake with a purpose. Mma Potokwane had always relied on Mr. J.L.B. Matekoni for help with mechanical problems at the orphan farm—particularly with the old pump, but also with vehicles, cookers, water systems, and indeed anything that involved moving parts. He had always given this help without complaint, even if the tasks that he was called upon to perform took up a great deal of his spare time. But that was what he was like, and Mma Ramotswe was proud of him for it.

She knew that this present of a cake was a prelude to a major imposition on her husband. Really! One would have thought that Mma Potokwane would grasp that others could see through her obvious tricks, but she seemed utterly impervious to any hints along these lines.