The main character Ray and his party of Aqutallion warriors embark on a quest to find and destroy Homncruse, the evil power threatening their world. Ray begins his journey alone on a tiny island, but eventually he meets his friends and fellow Aqutallion warriors: Tina, Cody, Leona and Dan, and even creates a town for the victims of Homncruse's evil to live. Villains encountered along tend to range from comical, such as Cat Boo and Badbad, to the elite generals of evil of Homncruse.

Initially all the teens are considered Pennon, the lowest rank of warrior. Before they can destroy Homncruse each of them must undergo a trial at their respective temples hidden around the world to receive the secondary powers of Banalet. Dan is an exception because he is the descendant of the prosperous Wise Man clan of Aqutallion. When Ray, Tina, Cody, and Leona achieve the status of Banalet and are united by the powers of Dan, Aqutallion is reborn and the group gains incredible powers.

The Aqutallions are not alone: eleven members of Kustera can be recruited to fight for the young warriors in their place for a time being. The Kustera are mostly meant to serve as a supplement to the Aqutallions, but their role in the story is vital to its progression. From the same temples where the Aqutallions gain their Banalet status, there is a Kustera only warp icon that sends the group to a dungeon where great treasures are hidden.

The Aqutallion

• Ray -- The leader of the Aqutallion warriors. Ray is a well rounded character that can deliver powerful attacks, both physical and magical. His magic consists of fire spells and healing spells.
• Tina -- Tina is the first friend Ray finds. While investigating Beegees Ray defeats a group of Badmen and rescues Tina; who from then follows Ray into battle. Although physically weaker than Ray, Tina can still wield some low level swords as well as staves and wands. Her true potential lies in her magic, which consists of healing, ice, and support style magic.
• Cody -- Cody is the second friend to be found. Initially he is being held captive by Garados and has been transformed into a Lion, and later turned to gold. Even before being restored to his human form, Cody travels with the group and can even battle, but he doesn't receive Pennon status until he is human again; he also can't use equipment or spells. Cody is the strongest of the warriors, and can wield stronger weapons such as axes and spears, along with swords and hammers. He also has wind magic as well as a couple of self supportive spells, but his abilities lie more in his physical strength than in magic.
• Leona -- Leona is the third friend to be found. After saving Cody, the party returns to Decatas to find Leona and her gang, but Dram kidnaps Leona before she can join. Fortunately, he doesn't take her far, and the party only has to break into the rich district to recover her. Leona is the fastest of the five warriors and can use some swords and claws. She also has access to lightning magic as well as a few supportive spells.
• Dan -- The final friend to be found. Unlike the other four, Dan is not Aqutallion, but a prosperous wiseman. Only when Dan joins the party will Aqutallion be reborn. Dan and his father reside in a secret tunnel beneath the well of Brasca; Dram discovers this and kills his father, but the four friends are able to defeat Dram and recruit Dan to their party. Dan is the youngest and shortest of the group. Physically weak, Dan makes up for this with a wide range of spells, including the best healing spells.

The Kustera

• David -- David serves as an early mentor for Ray on his home island and leads Ray to his starcrest. David is a purely physical character who can't use spells, but has a wide range of weapons and armor he can equip.
• Ryu -- After restoring the people of Beegees to their human forms, Ryu becomes available for recruitment in the town. Ryu is a ninja, which means he is exceptionally fast and can equip certain uniqe weapons. He also has access to some low level attack and healing spells
• Ben -- When arriving in Decates, Ben's wife can enlist the party's help in bringing Ben out of his drunken stupor to fight once again. Ben is a priest, and has a spell and equipment selection very similar to Tina's.
• Andy -- The boxer from Box Town who joins the party after the player defeats him and his brother. Like David, Andy is purely physical attacker, however he has a much more limited selection of weapons and armor to choose from.
• Arthur -- Andy's brother who resides in the town of Sleepers. Arthur is the exact opposite of Andy. He is very physically frail but has a wide range of attack magic he can use.
• Jubei -- A samurai warrior from Onsaka. He is recruited after the party defeats him. Jubei is another purely physical character. He has a wide selection of weapons to choose from, as well as a couple unique samurai weapons only available to him.
• Murray -- A wizard trapped in Moreyees. Murray joins the party once he is freed from the curse keeping him prisoner. Like Arthur, he is very frail physical, but can use powerful magic spells.
• Shark -- Found in a small house in the area of Bonzley. Shark will join the party only when all five Aqutallion warriors are together (after getting Dan essentially). Shark is very similar to David, having no magic but wielding a variety of weapons and armor.
• Evelyn -- The bunny thief in Elekees. Evelyn is like Leona, except she can't use magic.
• Kathy -- An Archer from the female town of Amaboss. Kathy is another physical character, except she uses bows as her weapons.
• Beth -- A medic from the female town of Amaboss. Beth is a powerful healer, but has no access to attack spells.

The villains

• Cat Boo -- The first available boss fight in the game. Cat Boo is originally an optional boss fight on Ray's home island. On the main continent Cat Boo becomes a common enemy.
• Badbad -- The leader of the Badmen. He has used a Dog Pill to turn the citizens of Beegees into dogs, and has the only other Dog Pill that can return them to normal.
• Ringo Brothers: Bingo and Leech -- These are lieutenants of Homncruse who have kidnapped the children from neighboring towns and are holding them for Homncruse.
• Garados -- The owner of the circus, and another lieutenant of Homncruse. He has kidnapped Cody and transformed him into a Lion to keep the Aqutallions from reuniting.
• Dram -- The 1st General of Homncruse. Dram is a giant man covered in plate mail and wielding giant axes. He is sent to destroy Dan, and ultimately prevent Aqutallion from being reborn.
• Booth -- The 2nd General of Homncruse. He is a troll like creature who wears a white hood and cloak. Booth is responsible for the destruction of Alazina, the town closest to his castle.
• Gara -- The 3rd General of Homncruse. The only female general, and the only general to look like a normal human. Gara is the sorceress who maintains rule of the city of Amaboss from her castle.
• Godem -- The 4th General of Homncruse. A winged dragon like creature, Godem is responsible for the destruction of the Aqutallions Temples (though not the dungeons beneath them.
• Homncruse -- The source of evil in the game and enemy in the final boss fight. His name may be a corruption of "Homunculus", and his creator Parakless a corruption of "Paracelsus".

A prototype of the U.S. version of Secret of the Stars has a slightly different title screen and has frequent gameplay glitches that make it unplayable.

The game was panned by many critics and gamers. On release, Famicom Tsūshin scored the game a 19 out of 40. One major complaint was about the separation of Aqutallion and Kustera parties; others complained that the Kusteras were never fully used in the course of the game. In addition, being required to level up two parties exacerbated what they believed to be a system that required excessive leveling to advance the plot, and the relatively high amount of enemies that are needed for the player's party to gain levels. Even the story, graphics and gameplay were attacked by many, calling them poorly written, NES-like, and simplistic. Since then, Tecmo has not made any similar role-playing games.