Everyone was talking late into the night at a reunion in Deongdeuk Park. Suddenly— THWACK!! One by one, they start falling unconscious.

Everyone wakes up to find themselves in a game center. While everyone is looking around in confusion, a voice rings out.

Among the 10 of you, two are Mafia, and there is one Doctor and one Police officer. The remaining six are Citizens. When night falls, everyone must return to their rooms. Shortly after, the Mafia, Doctor, and Police must perform their duties. The Doctor must come out first and place a sticker on one person's room. Then, the Mafia must come out and kill someone, excluding the room with the sticker. If the Mafia fails to kill within the time limit, the Mafia team is eliminated and the Citizen team wins.

Guest has a special privilege. You can choose your own role. You can be one of the four: Doctor, Citizen, Police, or Mafia.