In my story there's many references to pop culture and existing fictional characters. This is not just simple pop culture references like Supernatural, but straight up fictional characters playing some part in even small interactions with the film's characters. Like say one character grew up on specific movies and TV shows which played a part to her ideals and preferences as an adult. Or say a holodeck type technology from Star Trek exists and it's being used for various combat simulations which features various existing fictional characters. If I ever finish my script, would I immediately need to Simpsons and Epic Movie those characters (in which their names are slightly altered even though it's blatantly obvious who they're suppose to be) while the script is simply at the stage of being looked at? I'm all for trying to find some way to negotiate the real character into the film for some cameo if that's even possible in this day and age.