Create a story/script for a mobile app game

Industry: Entertainment
Topic: Game
Tone: Other
Outline & Structure: The game outline has already been created, we need to complete the story line.
The game has a structure similar to the game "The Wolf among us", meaning there is particular scenes where you are faced with options.
The story itself will have a feel like the infamous HBO series "The Wire" and also a journey into hip hop music and the main protagonist becoming a star.
Extensive research needed: yes
Extra notes: Please note myself and my partners have already got a brief overlay of what we require, so we will provide you a clearer summary of the direction the story needs to be in.