“Before that he occupied a cell in another part of the prison. He was not in cell 24.”

Here the head gaoler interrupted, and said:

“We changed him to another cell after his attempted escape.”

“But you, monsieur, you have seen him during those two months?”

“I had no occasion to see him. He was always quiet and orderly.”

“And this prisoner is not Arsène Lupin?”

“No.”

“Then who is he?” demanded the judge.

“I do not know.”

“Then we have before us a man who was substituted for Arsène Lupin, two months ago. How do you explain that?”