Hermione has always loved movies, even when she was really little. Her dad used to take her to see whichever move she wanted once a month for one on one time. She started doing the same with Rose and Hugo once they were old enough.
Ron never quite got why she was so in love with films though - like he'd watch them with her, but they were never that interesting to him. Until she made him watch Grease.
Hermione's favorites are mainly high fantasy, though she does really adore musicals.
Hermione tried to write her first film at 7 years old, which was kind of heavily plagiarized from Matilda. She kept at it, though, mostly just to unwind after work. She ended up writing a really great screenplay, and eventually Rose found it and made it her life's mission to make this movie become a reality. Finally, on Hermione's 50th birthday, Rose took her mom to see the premier for the film that she wrote.