The game’s story sees nine men and women locked up in an underground nuclear shelter with the goal of escaping. The nine characters are split up into three teams of three, in three separate sections of the shelter. To return to the outside and above ground, six passwords are required, but a password each time a person dies. In other words, escape is impossible unless at least six people die. Who will be sacrificed? Or is there another way. That choice is up to the player.
(The screenshots are from the PS Vita version.)