Action/Thriller - Breif Idea

We have decided to change our genre of our film clip to an action/thriller as we have all came up with a good idea combining some of thwe previous ideas we had.  We have changed our story line to a similar storyline to the film 'vantange point'. The breif idea is that we are goign to have a famous person opening a new housing estate on a building site, but unfortunatley they get assasinated, but does someone see the murderer? We then see teh murder packing away but enevr reveal his face! Does he get caught ? What was his motive? We have a small flashback and get a breif idea as to what is going on but it should leave the audience confused and usnure as to what is happening, making them want to watch the whole film. We decided to change our idea because we all felt more comfortable with this idea and all contributed part of the idea. Also because action and thriller was also one of the most popular with the audience we questioned.