Uta Sakura is a lively and energetic middle school student who loves singing. One day, while walking her dog, she encounters a cute, peach-like fairy named Purirun, who is searching for the Legendary Protectors "Idol Precure." Purirun's hometown, KirakiLand, was a peaceful, sparkly place but has been forced into darkness by the villainous Darkine, leader of the Chokkiri Gang. Uta decides to help Purirun search for cheerful and happy people to become the Precure so KirakiLand can become bright again. Suddenly, the Chokkiri gang arrive in Hanamichi Town, Uta's hometown, and steal the sparkles from the townspeople. Uta decides to illuminate the darkness with sparkles from her song and is granted the power to transform into the Legendary Protector, Cure Idol.

A decade ago, princess Krystal Novaty “Hime” Nokanatika traveled from another world to escape assassination attempts by an evil force. When she arrives in modern-day Japan, she encounters Haruto Satou. With him she shares a promise: he must forget what he has just witnessed, and the two will become friends. Now heading back to the Nokanatika Kingdom to fulfill her royal duties, Hime bids farewell to Haruto. However, when the young man suddenly remembers his first meeting with Hime, he rushes to the location where she first appeared and crosses the dimensional portal to be reunited with her. His arrival disrupts the marriage ceremony between Krystal and prince Marmarugias Gisaras. The wedding is brutally interrupted by the attack of an abyss monster who threatens the princess' life. Acting impulsively, Hime decides to exchange rings with Haruto, which grants her new husband light powers that permit him to slay the monster. Now dubbed as the Ring King, Haruto must marry four other princesses to acquire new magical powers and have a chance to prevail in his fight against the enemy of the world: the Abyss King.

Despite occasional setbacks, Operation Strix has remained on track to extract sensitive information from the enigmatic politician Donovan Desmond. To this end, spy Loid Forger has managed to maintain his pretend family consisting of his telepathic daughter, Anya; assassin wife, Yor; and their clairvoyant dog, Bond. Still the only one aware of everyone's true identities, Anya tries to sustain the family's cohesion while working to befriend Donovan's son Damian, her Eden Academy classmate. However, Anya's efforts instead earn her another Tonitrus Bolt, bringing her closer to getting expelled and jeopardizing the operation's success. Hearing the news, Loid faints from shock. In his unconsciousness, he reminisces about his tragic past and his journey to becoming a spy. Realizing what Operation Strix means to him and the world, Loid finds renewed motivation. Although they each work toward their own covert goals, the Forgers continue to cherish their chaotic yet blissful family life.

A squid-like creature, known as a Happian, leaves his home planet with the desire to spread happiness across the universe. He lands on Earth, but quickly finds himself in danger of captivity by its inhabitants. Fortunately, he is found by an unsmiling little girl named Shizuka Kuze, who feeds him and names him Takopii. Feeling indebted, Takopii decides to do everything in his power to bring a smile to her face. The task is easier said than done, however. Shizuka is bullied by her classmates, she does not have a father, and her mother is never home—though the gravity of these issues flies over the naive Takopii's head. Even so, Shizuka does have one source of happiness: her dog Chappy. The connection Shizuka and Chappy share only increases Takopii's desire to make the girl smile. While Takopii's attempts to lift Shizuka's spirits lead to unintended consequences, he is determined to take things into his own tentacles, test his understanding of human beings, and achieve his goal of spreading happiness.