In Yokohama, Fusion, Takehito Koyasu reappears and menaces the city with calamity, challenging the Pretty Cures to spring into action once more. A fierce confrontation unfolds as the Cures unite their powers, ultimately driving Fusion back but scattering its essence into fragments that drift across the streets and rooftops, leaving the threat only partly contained and waiting to be reassembled.
Ayumi Sakagami, Mamiko Noto a hopeful girl who looks up to the Pretty Cures, struggles to find friends at her new school. On her way home, she encounters a small, mysterious creature and names it “Fū-chan,” Sea Kumada a new companion whose presence slowly shifts Ayumi’s world from loneliness toward possibility.
Meanwhile, the fairy court—Tarte, Chiffon, Chypre, Coffret, Potpourri, Hummy, and Candy—gathers to assess the danger. They quickly notice that Fusion’s scattered fragments are seeking to recombine, so they set in motion a plan to enlist the help of the various Pretty Cure teams to hunt down every shard before the threat can rebound and devastate the city again.
During the search for the missing pieces, Miyuki encounters the Suite PreCure team: Hibiki Hojo Ami Koshimizu (Cure Melody), Kanade Minamino Fumiko Orikasa (Cure Rhythm), Ellen Kurokawa Megumi Toyoguchi (Siren/Cure Beat), and Ako Shirabe Rumi Okubo (Cure Muse). The four heroes transform and join the effort, trading blows with the fragments as they push to reclaim the stolen pieces and prevent Fusion’s return.
Ayumi, noticing people around her disappearing, sees Fū-chan’s confession—that he acted to shield her from harm. This revelation tests her resolve, and the moment becomes a turning point for her. With the combined power of the Smile PreCure! team and the help of HeartCatch PreCure! and Fresh Pretty Cure! squads, Ayumi steps forward and, for the first time, stands on equal footing with the legendary protectors.
As the battle intensifies, Ayumi undergoes a dramatic transformation into Cure Echo, marking a bold entrance into the broader Pretty Cure universe, aided by the Miracle Lights and the emergent alliance of past and present teams. Echo’s emergence rekindles her bond with Fū-chan, and together they face the looming threat. The remaining Fusion fragments rally to strike, but Fū-chan makes a selfless choice, sacrificing himself to empower the Smile team with the strength needed to push back the darkness and seal Fusion away once more.
In the aftermath, Ayumi’s world grows warmer and more hopeful. Surrounded by friends and the constellations of the many Pretty Cure families now connected by her courage, she finds her place and begins to build lasting friendships with her classmates, carrying the lessons of bravery, trust, and community into every new day.
