It certainly doesn't sound like we're talking about any specific films that you and your reader might have in mind. If I say that I don't like red cars, it means that I don't like cars that are red. There is no specificity in that statement whatsoever. All it says is that there are cars of different colors and I just don't happen to like ones that are red. A "that" clause does not necessitate the use of a definite article.
— Do you want to buy a car? But what color do you want your car to be?
— Any color will do except red. I just don't like cars that are red.
— What movies do you not like to watch?
— I don't like to watch movies that are about violence.
I guess, technically speaking, the statements red cars and cars that are red are indeed a little bit more specific than just cars, but they are still no more familiar than cars. Definite articles are used when you have some sort of familiarity or "preknowledge" of the things that you are talking about.