What Star Wars Knights of the Old Republic?
Technically they are based off a movie and they were both fantastic games. Some of the best characters I've ever seen in an RPG. I'm of the opinion that they actually put movies to shame.
I thought about that as KotOR is one of my favorite games of all time, but it's not really a direct tie-in to any of the movies and over the last 30 years or so Star Wars has expanded into much more than just a movie franchise, so I decided not to count it.