THERE WERE A FEW SIGNS later on, but nothing that Mma Ramotswe could put her finger on. At mid-morning tea time, she watched closely, but Mma Makutsi delivered the tea with no difficulty and their attention, anyway, was focused on dealing with comments on the new glasses. Mr. Polopetsi, of course, was polite, merely muttering, “New spectacles, Mma,” but Charlie, hooting with laughter, said, “Such small glasses, Mma! Does that make us all look very small? Are you sure you can see me, Mma? Look, here I am—over here. That tiny thing is me! And Mr. Polopetsi, here, must be invisible—he’s very small. Can you see him at all, Mma?”

Mma Ramotswe tended to ignore this sort of thing, and Mma Makutsi tried to do the same, but failed. She flashed an angry glance at Charlie and turned her back on him. Then a suitable retort occurred to her and she turned round to deliver it, but found herself face-to-face with Mr. Polopetsi, who now became almost effusive in his remarks. “Those are very nice glasses, Mma,” he said. “Extremely pretty, in fact. There was a very small girl at the shops the other day wearing glasses just like those.”

Mma Makutsi acknowledged the compliment with a nod of her head, although she was not sure whether she should be pleased or annoyed with the last part of what Mr. Polopetsi said. The rest of the tea break passed in a somewhat strained manner and Mma Ramotswe felt relieved when it was over and they could all get back to work. She had a few letters to dictate—and was Mma Makutsi hunched over her notebook more markedly than usual? She could not tell.

Then, half an hour or so later, Charlie came into the office. “Letter for you, Mma Ramotswe,” he said. “Somebody has just left it.”

People left notes for Mma Ramotswe, and she thought little of it. But when she took the envelope in her hands and began to slit open the flap, she felt a flush of foreboding. The letter was from that person; she could tell.

She read it carefully, aware of the fact that Mma Makutsi was watching her. So, fat woman, you think you know everything! You and that assistant of yours, with her stupid glasses—you know nothing about what you don’t know!

Mma Makutsi was about to say something, but Mma Ramotswe anticipated her. “Yes,” she said. “It is another one.” And she thought: Which stupid glasses? The original stupid glasses, or the new stupid glasses?

Mma Makutsi came over to take the letter. She peered at it, the paper close to her nose. The glasses don’t work! Mma Ramotswe said to herself. But any satisfaction she might have experienced on having her earlier suspicions confirmed was eclipsed by the gravity of the moment.

Mma Makutsi walked over to the door that led into the garage. “Charlie,” she shouted. “Please come through here.”