Loved by her friends Rikka Hishikawa and Alice Yotsuba for her kind-hearted nature and positive outlook on life, Mana Aida finds herself in the midst of chaos when extraterrestrial villains from the "Trump Kingdom" appear during a school trip. Using people's selfish desires, they create monstrous creatures that wreak havoc and destruction upon the world. In her quest to stop the carnage, Mana encounters "Cure Sword," a mysterious warrior from Precure. Mana soon discovers that she too possesses the power to become a Precure warrior, after meeting Cure Sword's fairy companions. When Cure Sword is outnumbered in battle, Mana steps up with unwavering courage and transforms into "Cure Heart," the embodiment of love. As she teams up with Cure Sword to defeat the invaders from the Trump Kingdom, Mana accidentally involves her friends Rikka and Alice. They too discover they possess abilities to transform into "Cure Diamond" and "Cure Rosetta," aided by their own fairy partners. Together, the girls stand united, fighting to protect the love that exists in the world from being destroyed.