"You think the dead we loved ever truly leave us? You think that we don't recall them more clearly than ever in times of great trouble? Your father is alive in you, Harry, and shows himself most plainly when you have need of him. How else could you produce that particular Patronus? Prongs rode again last night." 

It took a moment for Harry to realize what Dumblefore had said.

 Last night Sirius told me all about how they became Animagi," said Dumbledore, smiling. "An extraordinary achievement -- not least, keeping it quiet from me. And then I remembered the most unusual form your Patronus took, when it charged Mr. Malfoy down at your Quidditch match against Ravenclaw. You know, Harry, in a way, you did see your father last night.... You found him inside yourself." 

And Dumbledore left the office, leaving Harry to his very confused thoughts. 

Nobody at Hogwarts now knew the truth of what had happened the night that Sirius, Buckbeak, and Pettigrew had vanished except Harry, Ron, Hermione, Amelia, and Professor Dumbledore. As the end of term approached, Harry heard many different theories about what had really happened, but none of them came close to the truth. 

Malfoy was furious about Buckbeak. He was convinced that Hagrid had found a way of smuggling the hippogriff to safety, and seemed outraged that he and his father had been outwitted by a gamekeeper. Percy Weasley, meanwhile, had much to say on the subject of Sirius's escape.

 "If I manage to get into the Ministry, I'll have a lot of proposals to make about Magical Law Enforcement!" he told the only person who would listen -- his girlfriend, Penelope.

 Though the weather was perfect, though the atmosphere was so cheerful, though he knew they had achieved the near impossible in helping Sirius to freedom, Harry had never approached the end of a school year in worse spirits. 

He certainly wasn't the only one who was sorry to see Professor Lupin