Time turner
Hermione Granger received a time turner from Professor McGonagall in 1993, so that she could attend more classes in her third year than time would allow. Since McGonagall made her swear to not tell anyone about it, she did not mention it to Harry Potter or Ron Weasley until the end of the school year, when she and Harry used it to travel back in time and save Sirius Black and Buckbeak from certain death. Special permission from the Ministry of Magic had to be sought to allow Hermione to use one, but her academic record ensured that permission was given.
Time turner
Hermione Granger received a time turner from Professor McGonagall in 1993, so that she could attend more classes in her third year than time would allow. Since McGonagall made her swear to not tell anyone about it, she did not mention it to Harry Potter or Ron Weasley until the end of the school year, when she and Harry used it to travel back in time and save Sirius Black and Buckbeak from certain death. Special permission from the Ministry of Magic had to be sought to allow Hermione to use one, but her academic record ensured that permission was given.