If you make a movie called "Star Wars", sure. But (and please correct me if I'm wrong) making any derivative work, i.e. using the characters and stories - fan-f

If you make a movie called "Star Wars", sure. But (and please correct me if I'm wrong) making any derivative work, i.e. using the characters and stories - fan-fiction basically, would fall under the copyright regime. That's what I'm talking about.