The world is called Deep Earth. The world is a huge underground complex of cities and labyrinths. The world is populated by people who have never seen the sky and the sun in their lives. The world is dark and hostile, and knows no mercy. Technology is well developed in this world, but the society is ruled by a cruel law, dividing all the citizens into classes, depending on the their D-ratio - a form of identifying people and assigning to them a social status at the same time. This is the reality of mankind somewhere in a fantasy universe, where the hero Ryu is thrown into.
Ryu is a simple guard, a ranger with a low D-ratio - his job is to help to protect the citizens from genics - artificial monsters who have gone wild. During one of such routine patrols, Ryu runs into a mysterious silent girl named Nina, and saves her from a monster. Willing to protect her, Ryu discovers in himself a devastating power. He is now determined to do something for the society of Deep Earth - and perhaps to guide them to the surface of the planet...
'Dragon Quarter' is a radical departure from the previous titles of the long-running series and from standard console-style RPGs in general. The game is built as a huge dungeon crawler with no overworld map. The combat is much more strategic than usually: each character has action points (AP) which can be used to move around the screen during an enemy encounter and to perform a variety of combo attacks. There is no magic in the game and many of the items you find in dungeons are random. All the enemies are visible on screen. Depending on who first initiated a physical contact, your party or the enemies get an extra turn in battles. The game allows (and even encourages) the player to restart the game from the beginning, keeping the items and the party experience (extra experience you get from battles and from treasure chests, which you can store and then assign to any of the characters). The game also features a special counter - Ryu can use his traditional dragon transformation abilities, but the counter raises with each such transformation, and when the counter reaches 100, the game is over. Raising your D-ratio allows you to access new areas every time when you re-play the game.