After receiving the key to Brooklyn for saving their home, Mario and Luigi enjoy life as heroes for the first time. But then Bowser Jr., Bowser's son, has secretly emerged and taken control of the mysterious center of the universe, with a plan that threatens to expand the Koopa empire far beyond the Mushroom Kingdom.
To stop him, the brothers embark on a journey through strange worlds alongside Peach, Yoshi, to save Princess Rosalina, from protect her twinkles before they are consumed by darkness. Each step reveals more dangerous evidence, and a black market for forbidden stars will lead them to confront truths they never imagined.
