The game takes place in the year 2661. You play as Emerald "Dead Eye" Flint, a mercenary who potentially takes any job as long as it pays well and involves shooting. But because he was ambushed before the game starts, he has to work his way up with a shoddy ship which supports only light weaponry.
The major factions in the world of Aqua are:
- The Atlantean Federation
- The Clan Union
- The Shogunate
- EnTrOx Corporation, which has the monopoly on breathing gas
- The Tornado Zone, an anarchic group of pirates, mercenaries, and ruffians
This game contains examples of:
- Adam Smith Hates Your Guts: Averted near the end. As the entire world is in danger, prices drop by 90%, making it easy to max out the ship.
- Atlantis Is Boring: Averted big time.
- Cyber Punk / Bio Punk: The game's verse has quite a few elements of this.
- Dystopia: Not completely or deliberately, but humans sure have brought more than just naive high ideals with them underwater as a legacy of their past.
- Energy Weapon: You can outfit your ship with plasma weapons after you capture a Biont midway through the game. How a plasma weapon works underwater isn't fully explained, but all Biont technology is extremely advanced, anyway.
- Fantasy Counterpart Culture:
- The Atlantean Federation is a mashup of European, North and South American cultures and governments.
- The Clan Union consists mostly of various African, Arabic and Indian nationalities and resides primarily in the Indian Ocean.
- The Pacific Ocean is the pond of the Shogunate, a Japan-themed amalgam of East Asia and Russia.
- Hot Sub-on-Sub Action: Constantly, although the ships operate more like space fighters. The player always drives a fast, single-seat ship, and the standard weapons are rapid-fire guns.
- Lightning Bruiser: Biont ships are the fastest and toughest enemies. Even their bombers can outmaneuver you.
- Lovable Rogue: Flint, for obvious reasons.
- Mega Corp.: EnTrOx is powerful enough to have its own navy, EntroPol.
- Nintendo Hard: A later mission involves fighting superfast ships that are steered (in-game) by Artificial Intelligence, while a heavy current constantly throws your ship off course.
- Pirates: One of the few remaining underwater nations/powers are essentially a whole faction of them.
- Robot War: The Bionts attack humanity because they see themselves as the next evolutionary step
- Sliding Scale of Idealism vs. Cynicism: Pretty cynical on all fronts. Even more so in its direct successor, Aquanox.
- With This Herring: Your starting sub, of course.