"Who suspects me?" said Malfoy angrily. "For the last time, I didn't do it, okay? That Bell girl must've had an enemy no one knows about--don't look at me like that! I know what you're doing, I'm not stupid, but it won't work--I can stop you!"

There was a pause and then Snape said quietly, "Ah. . . Aunt Bellatrix has been teaching you Occlumency, I see. What thoughts are you trying to conceal from your master, Draco?"

Chapter 15