Long ago, seven Gods created the seven Sacred Stars, each one with its own purpose, that maintain balance in the universe.
They grant supreme powers to whoever captures them.
However, if they fall into the hands of someone with an evil heart, the world will be consumed by darkness and evil.
To prevent this, the Gods sealed them away in a Sacred realm.
However, since not everything is perfect, Bowser somehow managed to break into that Sacred realm and steal these stars to use them for his own purposes.
It is now up to Mario to rescue the stars and put an end to Bowser's plans once again.