"Because, although I do not know who Thusis really is, I do know that she is not going to marry you. And I do not believe you will ever see Thusis again after this herd of conspirators leaves Swiss soil."
I thought very hard for a while. Then: "Smith, I have become firmly convinced that Thusis is the original of The Laughing Girl! Find out who she was and you will learn who Thusis is. I'm certain of this. Now who was this Laughing Girl?"
"Nobody knows."
"Have you tried to find out?"
"Yes."
"Did you learn anything at all?"
"Not much."
"What did you learn?"
"That the photographs of The Laughing Girl are not permitted to be sold in Italy."
I looked at him, perplexed. He shrugged his shoulders: "Photographs for sale in European cities," he said, "are usually portraits of celebrities—actresses, demi-mondaines, royalties. Do you suppose Thusis to be one of these?"