She stared at him with an ashen face and gulped twice before she could speak.

“You are mad, Mr. Holmes⁠—you are mad!” she cried, at last.

He drew a small piece of cardboard from his pocket. It was the face of a woman cut out of a portrait.

“I have carried this because I thought it might be useful,” said he. “The policeman has recognized it.”

She gave a gasp, and her head dropped back in the chair.

“Come, Lady Hilda. You have the letter. The matter may still be adjusted. I have no desire to bring trouble to you. My duty ends when I have returned the lost letter to your husband. Take my advice and be frank with me. It is your only chance.”

Her courage was admirable. Even now she would not own defeat.