I sat silent, looking, not at him, but at the Cardinal's Necklace on the floor.
Then, suddenly, while I was still busy with the thought and dazzled at the revelation, while I sat bemused, before I could move, his fingers were on my throat, and his face within a foot of mine, glaring and working as he sent his strength into his arms to throttle me.

For his wife--and his name--he would fight a duel: for the sake of Marie Delhasse he would do murder on an invited stranger in his house.

I struggled to my feet, his grip on my throat; and I stretched out my hands and caught him under the shoulders in the armpits, and flung him back against the table, and thence he reeled on to a large cabinet that was by the wall, and Stood leaning against it.
"I knew you were a villain," I said, "but I thought you were a gentleman." (I did not stop to consider the theory implied in that.) He leaned against the cabinet, red with his exertion and panting; but he did not come at me again.

He dashed his hand across his forehead and then he said in hoarse breathless tones: "You shan't leave here alive!" Then, with a start of recollection, he thrust his hand into his pocket and brought out a key.

He put it in the lock of a drawer of the cabinet, fumbling after the aperture and missing it more than once.