That conversation came back to him now. If he were really serious about his duties, he would have warned Charlie of the folly of not completing his training. He would have spelled out to him the risks of starting one’s own business; he would have told him about cash-flow problems and the difficulty of getting credit. Then he would have gone on to warn him about bad debts, which presumably even taxi drivers encountered when people fled the car without paying or when, at the end of a journey, they confessed they did not have quite enough money to pay the fare and would five pula do?

He had done none of this, he reflected; he had said nothing. But his failure, and Charlie’s departure, were not the end of the world. If the taxi service did not work, then Charlie could always come back, as he had done the last time he had given up his apprenticeship. That had been when he had gone off with that married woman and had come back, his tail between his legs, when that affair had come to its predictable end. That showed how these young men worked, he thought. They bounced back.

Mma Makutsi’s departure, however, was a more serious matter altogether. Mma Makutsi resigned shortly before tea-time, when he and Mr. Polopetsi came into the office, their mugs in their hands, expecting to find the tea already brewed. Instead they found Mma Ramotswe sitting at her desk, her head sunk in her hands, while Mma Makutsi was putting the contents of a drawer into a large plastic bag. Mma Makutsi looked up as the men entered the room.

“I have not made tea yet,” she said. “You will need to put the kettle on yourselves.”

Mr. Polopetsi glanced at Mr. J.L.B. Matekoni; he stood in some awe of Mma Makutsi, and he was wary of her moods. “She is a changeable person,” he had explained to his wife. “She is very clever, but she is changeable. One moment it’s this; the next moment, it’s that. You have to be very careful.”

Mr. J.L.B. Matekoni glanced at Mma Ramotswe, but she, looking up, merely nodded in the direction of the kettle.

Mma Makutsi continued to busy herself with her task of emptying the drawer. “The reason why I did not put on the kettle is that I have resigned.”

Mr. Polopetsi gave a start. “From making tea?”

“From everything,” snapped Mma Makutsi. “So I suspect that you will be doing more investigating, Rra, now that I am going. I hope that Mr. J.L.B. Matekoni will be able to release you from your duties in the garage.”