“I never dropped anything in your study. That’s not mine. That’s Anne’s.”
“I know that,” I said.
“Well, why ask me, then? Anne must have dropped it.”
“ Mrs. Protheroe has only been in my study once since the murder, and then she was wearing black and so would not have been likely to have had on a blue earring.”
“In that case,” said Lettice, “I suppose she must have dropped it before.” She added: “That’s only logical.”
“It’s very logical,” I said. “I suppose you don’t happen to remember when your stepmother was wearing these earrings last?”
“Oh!” She looked at me with a puzzled, trustful gaze. “Is it very important?”
“It might be,” I said.
“I’ll try and think.” She sat there knitting her brows. I have never seen Lettice Protheroe look more charming than she did at that moment. “Oh, yes!” she said suddenly. “She had them on—on Thursday. I remember now.”
“Thursday,” I said slowly, “was the day of the murder. Mrs. Protheroe came to the study in the garden that day, but if you remember, in her evidence, she only came as far as the study window, not inside the room.”
“Where did you find this?”
“Rolled underneath the desk.”
“Then it looks, doesn’t it,” said Lettice coolly, “as though she hadn’t spoken the truth?”