The time: Space Century 3240. The place: The Algol Star System. It began when King Lassic turned evil and let hordes of hideous, magical creatures run amok on the three planets. When her brother was killed, Alis vowed to avenge his death and put an end to Lassic forever. Join her in a journey across time and space to worlds where creatures speak...where magic and science combine to take you on the ultimate video quest. Phantasy Star is total adventure role playing with towns full of people and shops...16 level dungeons full of traps and treasure...three companions who will help you if you find them and some of the most awesome graphics ever put in a video game.

The game introduces the star system of Algo, and its three planets Palma, Motavia and Dezoris. The system is in the grip of its evil ruler, King Lassic. A young girl, Alis, sees her brother die whilst trying to investigate King Lassic, and swears to avenge his death by ridding the system of the evil influence of Lassic. Alis is soon joined on her quest by Myau - a cat-like creature, Odin - a legendary fighter, and Noah, an Esper. Together they explore the planets of Algo, gathering mystical weapons and armour, battling with Lassic in his castle in the sky, and finally discovering the hidden darkness behind it all.