Group's Inital Idea For Horror Movie

The people in my group all had similar ideas for our horror movie trailer, and putting them together gave us a horror movie about religion, cults and self harm. In our film there is going to be 2 victims of the 'monster' which is the religion or cult. They get trapped in as they find a young girl laying in a country road, trying to help her and then search for help they come across this cult. The important part is that this young girl is actually the 'devil' of the cult, or who they worship. The couple don't know this, they think that the cult is trying to lure the young girl in   to hurt her. So the couple fight for the young girl, this obviously doesn't work and they become trapped into the cult. They become so brain washed with the religion and weird goings on that they start to self harm and then later on try and kill themselves. Also crucifixes are shown and used to torture the couple at the end. In the trailer we want to obviously give the audience a slight understanding of the characters and the film plot, but not too much. We didn't want to give the story away, so by quick flashy images and film towards the end of our trailer this creates suspense and interest of the film also creates questions in the viewers head. And to only find out what happens or what some of the footage shown is about is by going to watch it. We also wanted to use text in our trailer, in different parts we are going to give definitions of different words related to religion for example worship. This tells the audience its about religion and also makes them think about what could the film be about.