So its drama
A teaser kind of gives the tone of a movie so I will go from there:
It is a crime drama and I cant help thinking that you have come up with the scene and you are now trying to build the story from it yet it is the teaser. Correct me if I am wrong. And this is a turn of events. The "good guy" comes to the bad guy's place because he killed one of his men. Maybe you are giving out the ending. And at the end of the video there was only a shot we didn't see the actual shooting which would make it safe to say that he will not really be shot but outside help will come. seen it in every movie when the hero is stuck. Introduce new character? After the climax? I don't think its a good idea. Maybe I sound a little mean but I want to push you to some original material. I don't want you to spend a lot of time doing something that has already been done.