Our question is answered at 13:57 in the video. 

We sent a tweet to movie reporter and Youtuber Grace Randolph (Beyond the Trailer, Movie Math) about our idea and trailer.

We asked 'For our final year in school, we are making a film trailer for Media Studies coursework. The plot is a thriller and has a similar 'mystery killer' plot to Scream and Scream Queens. What do you think is most important in a trailer?'

@GraceRandolph Question! pic.twitter.com/ccyMgKg4bm

— daniel (@MrDSelenator) October 24, 2015

We received lots of advice that we will take on board. Grace regularly reviews movie trailers on her Youtube channel so we thought she was the person to go to when wondering what makes a good trailer. Grace also asked her viewers to put in the comments section any more ideas they have for us and to tweet her the trailer when it is finished which we plan to do.