"But why?" I exclaimed. "There's not a trace of blood!"
"Yes, yes, there is," replied Lupin, pointing to two or three drops that showed on the chest, through the open shirt. "Look, they must have taken him by the throat with one hand and pricked him to the heart with the other. I say, 'pricked,' because really the wound can't be seen. It suggests a hole made by a very long needle."
"Lupin took a tool from his pocket ... and inserted it in the lock"
He looked on the floor, all round the corpse. There was nothing to attract his attention, except a little pocket-mirror, the little mirror with which M. Lavernoux had amused himself by making the sunbeams dance through space.
But, suddenly, as the portress was breaking into lamentations and calling for help, Lupin flung himself on her and shook her:
"Stop that!... Listen to me ... you can call out later.... Listen to me and answer me. It is most important. M. Lavernoux had a friend living in this street, had he not? On the same side, to the right? An intimate friend?"
"Yes."
"A friend whom he used to meet at the café in the evening and with whom he exchanged the illustrated papers?"
"Yes."