A demoted police detective fights to find justice for her daughter after witnessing a grisly homicide that occurs near her newly assigned workplace.

Right now I’m confused. Does the grisly homicide have something to do with her daughter? It’s unclear. Also, if a police detective witnesses a homicide, they would start investigating it, wouldn’t they Do they do that? Or do they go on a separate quest to find justice for their daughter? I’m also wondering how the issue of their being ‘demoted’ connects to the other elements… that suggests a professional redemption arc, rather than anything to do with their daughter.