“Have you seen …” Mma Ramotswe began to call out, but then stopped. At the very same instant, she and Mma Makutsi had seen the tea-pot, sitting on top of an upturned oil drum.

Mma Makutsi was smiling with relief. “There it is,” she said. “Mr J.L.B. Matekoni must have made tea, as you said.”

She walked over to the oil drum and picked up the tea-pot, only immediately to replace it on the surface of the drum. Watching her, Mma Ramotswe instantly knew that something was very wrong. She hurried over to join Mma Makutsi, who was standing in mute dismay, peering into the open top of the tea-pot.

“Diesel oil,” Mma Makutsi muttered. “Somebody has filled it with diesel oil.”

Mma Ramotswe bent down and sniffed at the tea-pot. The unmistakable smell of diesel was strong in her nostrils.

“Oh!” she exclaimed. “Who has done this? Who has done this?”

She turned and looked at the three men. They stood there, two of them looking puzzled and a third looking sheepishly down at his overalls.

“Charlie!” shouted Mma Ramotswe. “You come over here right now! Right now!”

Charlie sauntered over, accompanied by Mr J.L.B. Matekoni.

“What is all this?” asked Mr J.L.B. Matekoni, wiping his hands on a piece of cotton lint. “What is all this fuss?”

“He’s put diesel oil in my new tea-pot,” wailed Mma Makutsi. “Why did he do that?”

There was a defensive note in Charlie’s voice. “I was draining a tank,” he explained. “I had nothing to catch the diesel. So I found that thing in the office and it was empty. I thought I’d use it. Don’t worry, I’ll wash it.”

“Can’t you see it’s a tea-pot?” snapped Mma Ramotswe. “Can’t you see even that?”

“It is not the usual tea-pot,” said Charlie defiantly. “The tea-pot we use does not look like that.”

“That’s because it’s my new tea-pot,” interjected Mma Makutsi. “You stupid, stupid boy. You are more stupid than a cow.”

Charlie bristled at the insult. “Don’t you call me stupid, Mma. Just because you got ninety per cent.”

“Ninety-seven per cent,” shouted Mma Makutsi. “You can’t even get that right. You are as stupid as a warthog.”

“She must not call me a warthog,” Charlie protested to Mr J.L.B. Matekoni. “Boss, you cannot let this foolish woman call me a warthog. She is the warthog. A warthog with big round glasses.”

Mr J.L.B. Matekoni wagged a finger. “You must not say that, Charlie. You are the one who is in the wrong here. You put diesel oil in Mma Makutsi’s new tea-pot. That is not a clever thing to do.”

Charlie took a deep breath. His eyes had widened now, and his nostrils were flaring slightly. It was clear that he was very angry.

“I may be stupid,” he said. “But I am not stupid enough to stay in this useless garage. That’s it, Boss. I quit now. Right now.”

Mr J.L.B. Matekoni grasped the apprentice’s arm in an attempt to reassure him, but was brushed off. “But what about the apprenticeship?” he said quietly. “You cannot give that up.”