I recently watched The Prime of Miss Jean Brodie, a movie I was completely unfamiliar with. It was released in 1969 and Maggie Smith won an Oscar for Best Actress in a Leading Role in 1970 for her performance. Yes, the same Maggie Smith who plays Minerva McGonigall in the Harry Potter movies.
The story and acting aside, one thing that stood out--and Josh was the first to make this connection--was that Jenny, a student and trusted confidante who betrays Miss Brodie at the end, looks like a female version of Harry Potter but minus the scar.
Purely an observation of coincidence not intended as a basis for choosing whether or not to trust an adolescent who dons black-framed, rounded lense spectacles. Look for the scar instead.