Batman movies have shown, even back in 1966's Batman: The Movie, that the best thing about the character has been the world he inhabits. This could be seen from the side characters like Vicki Vale or Harvey Dent or villains like The Joker and Catwoman. Even still, when looking at the Batman tetralogy, there's always been some speculation as to how connected the movies are, especially because Tim Burton's gothic style was nothing like Joel Schumacher's colorful and campy Gotham City.
Source：https://www.cbr.com/batman-returns-batman-and-robin-easter-egg/
