Taking place in a science fantasy universe, the story centers around a young man named Claude C. Kenny, a cadet from a space-faring Earth organization who is stranded on an undeveloped, medieval-level planet. There, he meets several companions and must stop a plot from an evil organization that spans multiple worlds before finding his way home.
The game gives the player the choice of playing as the human Claude or the Nedian Rena, with the journey evolving and ending differently depending on the choices one makes. There are ten other playable characters in the game, though the player can only recruit six of them to fill out their eight-member party, and some recruitment choices will make other characters no longer available. The Second Story's gameplay is broadly similar to that of most RPGs. The player goes from town to town and dungeon to dungeon, following the central story and occasionally branching off to perform side quests. Characters gain experience points from battle and level up as a result, becoming gradually stronger as time passes and more battles are fought.
Star Ocean: Second Evolution is an enhanced remaster featuring new skills, combat system, including a new playable character and 13 new endings (for a total number of 99–100 endings). Production I.G provided new artwork and animated cutscenes for the game. There are new voice actors and extensive amounts of new, fully voiced dialogue. The opening song is "Start", performed by Scandal. Numerous small changes were made such as replacing a cross with a pillar, a death scene now cuts to black, and child ages were changed to be older.
Second Story R is a remake with no anime cutscenes, a new opening movie, new codex's, and completely new gameplay and graphics.