As they approached the printing machine, the two young men stopped what they were doing. One flicked a switch and the machine ground to a halt. Without the noise it had been making the works now seemed unnaturally quiet, apart from the radio in the background somewhere which could still be heard churning out the insistent beat of a rock tune, the sort of music that Mma Ramotswe described as the sound of an angry stomach.

The young men were dressed in work overalls and one of them now took a cloth out of his pocket and wiped his hands on it. The other, who had a large mouth, which he kept open, reached a finger up to fiddle with his nose, but thought better of it and dropped his hand to his side.

“This lady is a client,” said Teenie. “She is very interested in printing. You could tell her about the new machine. She is called Mma Makutsi.”

Mma Makutsi smiled encouragingly at the young men. She tried to keep her eyes off the face of the young man with the gaping mouth, but found that she could not; such a deep space, like the mouth of a cave, allowing one to see straight into his head. It was fascinating, in a curious, uncomfortable way.

The printer who had wiped his hands on the cloth leaned forward to shake hands with Mma Makutsi. He spoke politely to her, and told her his name. While this was happening, Mma Makutsi felt the eyes of the other young man on her. She glanced at him, but saw only the open mouth. Absurdly, temptingly, she wanted to put something into it: pieces of paper, perhaps, small erasers, anything that would block it up; it was ridiculous.

Then the young man spoke. “You are that lady from the detective agency,” he said. “That place on the Tlokweng Road.” The sound of his voice may have come from his mouth, but to Mma Makutsi it seemed that it really came from somewhere below, down in his chest or stomach.

Mma Makutsi looked at Teenie, who turned to stare up at her in blank surprise. “I am that lady,” she stuttered. “Yes.”

There was silence. Mma Makutsi was momentarily at a loss as to what to say. She felt an intense irritation that this young man, with his disconcerting mouth, should expose her so quickly. But then she began to wonder how he knew. It was flattering to think that she was well known, a public figure almost, even if it meant that she would be unable to carry out enquiries quite as discreetly as she hoped; certainly this enquiry was ruined now, as everybody here would know within minutes who she was.

Her surprise turned to anger. “So I am that lady,” she snapped at the young man. “But that means nothing. Nothing at all.”