They all trooped down to the Great Hall, quickly fixing their hair along the way. "The teachers and I need to conduct a thorough search of the castle," Professor Dumbledore told them as Professors McGonagall and Flitwick closed all doors into the hall. "I'm afraid that, for your own safety, you will have to spend the night here. I want the prefects to stand guard over the entrances to the hall and I am leaving the Head Boy and Girl in charge.