‘It’s called a Time-Turner,’ Hermione whispered, ‘and I got it from Professor McGonagall on our first day back. I’ve been using it all year to get to all my lessons. Professor McGonagall made me swear I wouldn’t tell anyone. She had to write all sorts of letters to the Ministry of Magic so I could have one. She had to tell them that I was a model student, and that I’d never, ever use it for anything except my studies … I’ve been turning it back so I could do hours over again, that’s how I’ve been doing several lessons at once, see? But …