999: Nine Hours, Nine Persons, Nine Doors

Nine people have been kidnapped by a mysterious person called Zero and are forced to participate in a survival game called the "Nonary Game". Each player has a bracelet numbered 1–9, which they must use to pass through doors numbered 1–9 to reach the exit before 9 hours run out and the ship in which they are in sinks. Various puzzles must be solved in order to advance through the ship and reach the exit, while uncovering the mysteries behind the Nonary Game. [Edited from a post from ntsc-uk]

"From somewhere far away, Junpei could hear the sound of metal squeaking. He felt his stomach tighten. There were a thousand things the sound could have been, but none of the things he could think of were good. In an attempt to distract himself, Junpei looked around the room once more. Set in the wall directly in front of him was a slightly dirty iron door. The first thing Junpei noticed about the door was the number roughly emblazoned across it. On the surface of the door, in red paint, someone had written... 5"