The next morning, Draco heard Mcgonagall screaming. "How dare you, Mclaggen? Petrifying a girl in the middle of the night!! Expulsion is the only-" she began, but was interrupted by Albus Dumbledore. "No." he said firmly. "But headmast-" she began again. "Mr. Mclaggen was serving detention with me. Isn't that right Cormac?" Cormac slowly nodded.
"Then who did it?"
"I would like to inspect all your wands"
"Albus, wh-"
"Priori-"
"Incantatem.( or however it's spelled!)Very smart, Albus."
Professor Dumbledore smiled.