During a meteor shower, a star‑shaped alien crash‑lands in the home of Lala Hagoromo and Hikaru Hoshina, forcing the girls to care for the playful being they christen Yuma. Their bond starts rocky, yet Lala and Yuma eventually find common ground in their shared love of music and adventure. The alien's powers amaze the girls, who quickly learn to harness them while exploring.
When alien hunters intent on capturing Yuma appear on Earth, the girls discover that Yuma holds deeper secrets. Their resolve to protect Yuma draws them into a dangerous alliance, testing friendship. While safeguarding Yuma, the Star☆Twinkle Precure become embroiled in a cosmic conflict that threatens the galaxy. Will Yuma sense the Precures" feelings through their song, and can they sacrifice enough to protect all that matters?