Musashino, Tokyo. An elementary schooler repeatedly attacks people in the streets. Known only to the public as "Lil Slugger", none of the victims can recall the young boy's face and only three distinct details are left in their memories: golden inline skates, a baseball cap, and the weapon: a bent golden baseball bat. Detectives Ikari and Maniwa set out to track down the perpetrator and put an end to his crimes.

Hikaru Shindō is just a normal 12-year-old boy, but one day he's rummaging through his grandfather's things to see if he can find something to sell and pulls out an old go board. A ghostly apparition appears out of the board and tells Hikaru his sad story. His name is Fujiwara no Sai, a man who was a go instructor to the emperor of Japan a thousand years ago. However, because of the bad sportsmanship of his opponent during a game, Sai was accused of cheating and banished from the city. With no livelihood or any other reason to live, Sai committed suicide by drowning himself. Now, he haunts a go board, and wants to accomplish the perfect go game, called the "Hand of God" which he hopes to do through Hikaru. If Hikaru will be able to do it or not (or even wants to) will have to be seen.

Tsubomi Hanasaki is a girl in the second grade of middle school who likes flowers and plants. One day she experiences a weird dream. In that dream, a large blooming tree appears. Suddenly, it loses all of its flowers and 2 fairies appear. A few days later after Tsubomi has transferred to Myoudou Academy, suddenly the fairies from the dream appear before her and plead to Tsubomi to become the legendary warrior Pretty Cure, and protect the Heart Tree. However, Tsubomi declines as she doesn't think that she would be able to do that. However, a mysterious enemy suddenly strikes and steals the Heart Flower of her classmate, Erika Kurumi. Now she doesn't have a choice. To retrieve Erika's Heart Flower, she has to transform into a Pretty Cure and fight. Working up the courage, Tsubomi turns into Cure Blossom and a new chapter of Pretty Cure begins!

Astro is a robotic boy created by Dr. Tenma to replace his late son. When Tenma destroys his laboratory and shuts down Astro, the Ministry of Science revives him and tries to give him a normal life as a 6th-grade student who occasionally helps keep renegade robots from causing harm.