PreCure Splash Star

The series was conceived after staff debated whether to continue with the same characters from the previous PreCure series or introduce entirely new ones; the decision to replace the main characters was unprecedented for a girls' anime series and sparked intense internal discussion.

The decision to create new characters was partly driven by concern that continuing with the original cast would lead to diminishing appeal after a few years, and by producer Ten Washio's awareness that director Daisuke Nishio was exhausted after directing the original series for two consecutive years.

Producer Ten Washio chose Toshiaki Komura as the new series director specifically because Komura understood children's animation well and would avoid depictions parents dislike, such as wasting food, which resulted in the show having a softer overall atmosphere.

Compared to the flashy, aggressive fight choreography of the previous series Max Heart, director Komura felt that style was too intense for a Sunday morning show, especially after complaints that the action was too violent and scared children, so Splash Star emphasized light effects and a 'defense' rather than 'attack' image in battles.

Character designer Akira Inagami conceived the two new heroines with a 'little sister' concept, deliberately making them appear younger-looking than the protagonists of the previous series since he felt surpassing the original duo would be difficult.

The show's merchandise sales fell well short of Bandai's targets: the initial annual goal of 9 billion yen was revised down to 7 billion yen after the first quarter, and the final result came in at only 6 billion yen (about 49% of the previous year), which was partly attributed to the risky decision to replace the main characters.

Due to poor commercial performance, Splash Star did not get a planned second year of episodes (unlike the two previous series which each ran two years); instead the franchise moved on to an entirely new concept with Yes! PreCure 5, and character variations originally intended for the unmade second year were repurposed as the mid-series forms Cure Bright and Cure Windy.

Splash Star was the last entry in the PreCure franchise produced without high-definition, as the following series Yes! PreCure 5 switched to HD production.

The series' setting was designed with Norse mythology as a hidden underlying motif, including the concept of the World Tree that sustains all worlds.

The fictional town of Yunagi in Unabara City was explicitly stated to be modeled after the real-life areas of Shonan and Kamakura.