I'm The Mafia

With enough members, roughly ten, pick who would take on the role as the mafia, the doctor, and the police or detective. The rest would be the civilians. The roles are determined by the host of the game. The objective of the game is to kill the mafia or the mafia would kill the citizens. The winner is determined by who gets killed the most in terms of the mafia or if the mafia is killed. A simple harmless game. That's what Rob and Zyfe thought when their friends from AU told them they were playing a game. But, how can a simple game lead to so many revelations, betrayals, doubts, and even murders? And just who exactly are the "mafias" behind this?