Their conversation was interrupted at this intriguing point by the entry into the office of Mr. Polopetsi, the half-trained mechanic employed by Mr. J.L.B. Matekoni in the garage, who occasionally helped out in the detective agency. Mr. Polopetsi had been taken on as an act of charity but had proved himself to be a valuable member of staff, now quite capable of carrying out a full service on most makes of car and every bit as accomplished as the apprentices in handling a number of other mechanical procedures. He came in now bearing the chipped white mug from which he drank his tea.

“I see that you have had doughnuts,” he said, looking pointedly at the greasy wrapping paper on the side of Mma Makutsi's desk. “I thought doughnuts were for Friday.”

“There has been a change of policy,” said Mma Makutsi. “A forward-looking business must be flexible.”

Mma Ramotswe laughed. She was looking at Mr. Polopetsi, and she remembered that he was often rather good at shedding light on a problem. His ideas were frequently unusual but quite astute for all their unexpectedness.

“Tell me, Mr. Polopetsi,” she asked. “How would you deal with this thing, Rra?” She passed him Mr. Molofololo's list of football players. “Do you recognise that?”

Mr. Polopetsi ran an eye down the list of names and then looked up with a grin. “The Kalahari Swoopers, Mma. That's who these people are.” He pointed to one of the names. “Quickie Chitamba. He used to live out at Tlokweng, near my cousin. They saw him sometimes, driving past the house. His wife is a friend of my wife's brother.”

Mma Ramotswe gave a casual wave of the hand. “Yes,” she said. “Quickie Chitamba. I've seen him play.”

Mr. Polopetsi looked at her in astonishment. “I would never have guessed, Mma. You're interested in football, Mma Ramotswe? I didn't know that!”

“There are always new things to find out about a person,” said Mma Makutsi.

“Oh, I know that,” said Mr. Polopetsi. “It's just that I can't see Mma Ramotswe at a football match.” He closed his eyes, the better to envisage the scene. “No, Mma, I can't see you there. I just can't.”

Mma Ramotswe laughed. “And that is not surprising, Rra. I have only been once. You see, we're working on a football case now. You may smile, Rra, but that is what we're doing. We are football detectives now.”

While Mma Makutsi made Mr. Polopetsi a cup of tea, Mma Ramotswe explained the background to the Molofololo case. Mr. Polopetsi listened intently, raising an eyebrow at the allegation of treachery. When she had finished, he shook his head in wonderment. “I noticed that they were not doing very well. I thought that maybe their coach was trying new tactics, or something like that. I would never have dreamed that there was somebody deliberately losing. That is very serious, Mma. Ow!”

“So, Mr. Polopetsi,” Mma Ramotswe said. “So here are Mma Makutsi and I sitting and wondering where to start. And I said to Mma Makutsi that we should look at anybody in the team who appears to have more money than one might expect. That's always a clue, I think.”