Throughout the movie "Gone Girl", there is an orange house cat that appears in numerous scenes. Is this some kind of symbolism?
It seems to initially be a nod to a well-known book on screenwriting. The book has some very specific advice when it comes to getting an audience to side with a character.
In a 2014 interview at the NY Film Festival, Gone Girl author/screenwriter Gillian Flynn had this to say when questioned about the movie's "cat character":
There’s a screenplay book called Save the Cat. It’s all about making your character likable. In the first 10 minutes he should do something that makes you like him. I enjoyed that in the first 10 minutes [of Gone Girl], he literally saves the cat. I love that he’s so devoted to his cat.
So directly from the source, that appears to be the reason for Gone Girl's feline featured player. Some critical theories argue that the cat functions onscreen as an impartial third party to the action, viewing events dispassionately from a distance. However, no comment from any of the creative forces involved in the film has ever confirmed this theory, or even mentioned it.