Our groups initial idea for our horror trailer

The horror trailer begins with a young girl being given a music box as a birthday present, the same day or perhaps a few days later, she goes into her bathroom, plays the music box whilst in the bath. We cut to her drowning or we just see her dead body. (undecided as just seeing her body would be more mysterious, however in a horror trailer the struggling would have more of a scary impact on the audience.) The music box then gets possessed by her spirit. We can see this happening by perhaps a closeup of the music box.
We cut to many years later, perhaps shown by inter-titles (the music box becoming a family heirloom) the music box is passed down the family to a teenage girl. Every time the music box is played by the girl the spirit enters into her body or haunts her throughout the film. We see the effects it has on her and the ending we see her drowning, relating to the first part of the trailer.

We have decided to have two sections to our horror teaser trailer, I feel this is effective as it gives the audience an insight to what is happening but will hopefully not give too much away.