King Neptune's Adventure is a game for the Nintendo Entertainment System which revolves around an ancient event occurring every 100 years, where a treasure mysteriously vanishes at the sighting of the Star of Tritan. The game follows King Neptune, guided by the spirit of the seven seas, in his quest to recover the eight lost treasures and restore the orb of peace to his marine realm.
One thousand years ago, on the equinox of the new star of Tritan, the golden crown of Polaris was stolen. And so it has been every 100 years, no matter what precautions were taken, no matter where the treasure was hidden, when the Star of Tritan appears, another treasure disappears. With the spirit of the seven seas to guide him, King Neptune must find the 8 stolen treasures and return the orb of peace to his undersea kingdom!