“Severus,” said Dumbledore, turning to Snape, “you know what I must ask you to do. If you are ready . . . if you are prepared . . .” “I am,” said Snape. He looked slightly paler than usual, and his cold, black eyes glittered strangely. “Then good luck,” said Dumbledore, and he watched, with a trace of apprehension on his face, as Snape swept wordlessly after Sirius. It was several minutes before Dumbledore spoke again.
