In the Star Twinkle PreCure series, aliens seek to revive the scattered Star Princesses and avert the universe's descent into darkness by aiding the newly transformed Cure Star and her companions in their fight against the Notraiders.

The Starry Sky World is the home to the twelve Star Princesses who are based on the Zodiac signs and maintain order in the universe. But when the Notraiders attack the Star Palace, the princesses scatter themselves across the universe as the Princess Star Color Pens. Seeking to revive the princesses and avert the universe from being consumed in darkness, the aliens Lala and Prunce travel with the fairy Fuwa to Mihoshi Town) on Earth where they meet the imaginative Hikaru Hoshina. Receiving a Star Color Pendant and one of the Star Color Pens, Hikaru transforms into the legendary PreCure, Cure Star. Joined by Lala and two other girls, Elena and Madoka, as well as the shapeshifting catlike alien, Yuni, Hikaru leads the Star Twinkle PreCure as they seek to revive the Star Princesses and fight against the Notraiders.