Citizen X takes place at the beginning of the 20th century in a small city east of the Urals. Due to an avalanche all citizens were separated from civilization. To make matters worse a horrible vision came true. Zombies attacking during the night reduce the number of decent citizens. Does the attorney solve this mystery? Time works against the citizens. The role of the moderator is played by a DVD or MP3 file. At the beginning of the game each player starts with a character and a weapon. Similar to Werewolves game roles are called, but not by a game master, by the DVD. During night all characters have their eyes closed. Due to this players learn information about each other. Zombies try to overwhelm other characters. After this the day phase starts. The large group separates into groups of two that can exchange info with trustworthy people. Clever negotiation is important.