The genre of our film is psychological thriller and they have there own conventions. A usual feature of a psychological thriller is that there is some sort of mystery or drama in the opening sequence. We have this mystery and drama in our opening sequence when our ghost character which can't be seen which creates the mystery.
As said in my Directors chair, a cructial convention of a psychological thriller is that it includes flashbacks or montages. We include a montage of images at the beginning of our opening sequence to set a mood of unhappiness.