And we all started up in affright, when the Lady in Black began to laugh--the frantic laugh of a madwoman! She ceased as suddenly as she had begun and a horrible stillness followed. We dared look neither at her nor at each other! She was the first to speak. “It is all over!” she said. “Forgive me: I won’t laugh again.” And then Rouletabille said, speaking in a very low tone: “It will be over when we know how he got in.” “What good would it do?” replied the Lady in Black. “It is a question to which he alone knows the answer. He is the only one who could tell us and he is dead.” “He will not be truly dead for us until we know that,” responded Rouletabille. “Evidently,” said M. Darzac, “so long as we do not know that, we shall be uneasy and he will be there in our minds. He must be driven away! he must be!” “Let us try to drive him away then,” said Rouletabille. And he went to the Lady in Black and gently took her hand in his and attempted to draw her into the next room, begging her to lie down and rest. But Mathilde declared that she would not go. She said: “What! you would drive Larsan away and I not here!” And her voice sounded as though she were about to laugh again. I made a sign to Rouletabille not to insist upon her absence. Rouletabille opened the door leading into the corridor and called Bernier and his wife. They did not wish to enter, but we insisted on their doing so, and a general consultation took place from which we deduced the following facts: (1) Rouletabille had visited the apartment at five o’clock and searched behind the panel and at that time there was no one in the room. (2) After five o’clock, the door of the apartment had been twice opened by Pere Bernier, who alone had the right to open it in the absence of M. and Mme. Darzac. The first time was at five o’clock to permit M. Darzac to enter; the next at eleven o’clock to admit M. and Mme. Darzac. (3) Bernier had locked the door of the apartment when M. Darzac went out with us between a quarter past and half past six. (4) The door of the apartment had been locked and bolted by M. Darzac as soon as he entered his room, both in the afternoon and in the evening. (5) Bernier had stood guard before the door of the apartment from five o’clock till eleven o’clock with a brief interruption of not more than two minutes at six o’clock. When we had discussed and fully established these facts, Rouletabille, who was sitting at M. Darzac’s desk taking notes, arose and said: “So far, it is very simple. We have only one hope. It is in the few moments that Bernier was off guard about six o’clock. At least, at that time, no one was in front of the door. But there was someone behind it. It was you, M. Darzac. Can you reiterate, after having thoroughly searched your memory, that when you went into your room, you instantly closed the door and drew the bolt?”