Chihaya Ayase, a strong-willed and tomboyish girl, grows up under the shadow of her older sister. With no dreams of her own, she is contented with her share in life till she meets Arata Wataya. The quiet transfer student in her elementary class introduces her to competitive karuta, a physically and mentally demanding card game inspired by the classic Japanese anthology of Hundred Poets. Captivated by Arata's passion for the game and inspired by the possibility of becoming the best in Japan, Chihaya quickly falls in love with the world of karuta. Along with the prodigy Arata and her haughty but hard-working friend Taichi Mashima, she joins the local Shiranami Society. The trio spends their idyllic childhood days playing together, until circumstances split them up. Now in high school, Chihaya has grown into a karuta freak. She aims to establish the Municipal Mizusawa High Competitive Karuta Club, setting her sights on the national championship at Omi Jingu. Reunited with the now indifferent Taichi, Chihaya's dream of establishing a karuta team is only one step away from becoming true: she must bring together members with a passion for the game that matches her own.

Chihaya Ayase is obsessed with developing her school's competitive karuta club, nursing daunting ambitions like winning the national team championship at the Omi Jingu and becoming the Queen, the best female karuta player in Japan—and in extension, the world. As their second year of high school rolls around, Chihaya and her fellow teammates must recruit new members, train their minds and bodies alike, and battle the formidable opponents that stand in their way to the championship title. Meanwhile, Chihaya's childhood friend, Arata Wataya, the prodigy who introduced her to karuta, rediscovers his lost love for the old card game.

At his father's command, Oguna, the youngest prince of Yamato, sets out to kill Takeru Kawakami, the leader of Kumaso. However, upon arriving in Kumaso territory, he is injured by the stray arrow of a young local woman named Kajika who is hunting game. Eager to compensate for the terrible mistake, she escorts Oguna to her village to treat his wound. But as the two rapidly fall in love, the prince makes a disturbing discovery: Kajika is Takeru's younger sister! Conflicted between his newfound love and family duty, Oguna seeks advice from the Phoenix, a legendary immortal bird that serves as Kumaso's guardian. Compelled to make a decision, will the Yamato prince betray his own for the woman he loves, or will he murder Kajika's brother as commissioned? Inspired by the Yamato Takeru Japanese legend, Hi no Tori: Yamato-hen chronicles the tragic story of an ill-fated couple, showing how true love can conquer hate and adversity even among the greatest of uncertainties.

In deep space, four astronauts discover that their colleague Makimura has mysteriously died shortly following a cryptic note about his imminent murder. Though horrified by the news, the inoperable state of their spaceship leaves the crew no time to grieve, and they evacuate via escape pods. Determined to identify the culprit, the survivors begin to suspect fellow crewmate Kizaki, on account of a rivalry between himself and Makimura regarding the only female team member, Nana Ichinomiya. However, to their bewilderment, they notice Makimura's pod following them, yet failing to respond to attempts at contact. As the astronauts try to interpret their perplexing circumstances, they learn there are more inconceivable stories about their lost teammate, one involving the Phoenix, a mysterious bird said to have the ability to grant immortality. It is not until they crash into a seemingly deserted planet that the crew will finally uncover the sinister truth behind Makimura and his suspicious pod. Set in a distant future, Hi no Tori: Uchuu-hen illustrates the cruelty of human beings passionately in pursuit of their own desires without any regard to the consequences.