Suzume - How much meaning must we overcome before we reach our destination?

Suzume, a high school girl, lives with her aunt in Kyushu. One day, on her way to school, she encounters a young man searching for an abandoned door. Suzume directs him towards an abandoned onsen resort. Curious, she follows him and discovers a mysterious door. Peeking inside, she glimpses another world but finds herself unable to fully enter, even when she steps through. She trips over a cat statue, which unexpectedly transforms into a real cat. Back at school, Suzume notices smoke coming out from the resort, which is invisible to her classmates. Sensing an emergency, she rushes back to the site. The young man is struggling to close the door, and Suzume joins him, successfully sealing it shut. The injured young man is taken home by Suzume to take care of his wounds. He reveals himself to be Souta, a "Closer" tasked with shutting doors across Japan to prevent disasters. Suddenly, the cat from the resort reappears and magically turns Souta into a three-legged chair. The cat, named Daijin, is revealed to be a keystone, the only one who is capable of restoring Souta to human form. Suzume confesses to Souta that she inadvertently freed Daijin at the abandoned resort.

Determined to rectify her mistake, Suzume joins Souta in pursuing Daijin. Their chase leads them to encounter a worm, which they manage to contain by closing another door. Learning that Daijin is in Kobe, they hitchhike their way there, finding themselves unexpectedly babysitting for a grateful mother. They eventually locate Daijin, who leads them to an abandoned amusement park, where their attempts fail.

Daijin's trail leads them to Tokyo, prompting Souta to invite Suzume to his home. Souta explains his family's legacy as Closers, passing down the responsibility through generations. He warns of the devastating potential of the worm. Recognizing the urgency, they attempt to restrain Daijin, but the cat unexpectedly transfers its keystone role to Souta. Now a keystone himself, Souta can no longer live as a normal human. Torn between her desire to have Souta back and the need to prevent catastrophe, Suzume reluctantly uses him to seal the worm.

With the immediate threat averted, but Souta gone, Suzume catches a glimpse of him in the Ever-after, a realm she cannot enter. Seeking answers, she visits Souta's grandfather in the hospital. He reveals that Suzume's ability to perceive the Ever-after stems from a childhood experience where she briefly entered it. The only way to return is through the same door she used before. Suzume struggles to recall the memory, eventually realizing the door's location at her old home in Kyushu. She reunites with Souta's friend, Tomoya, and her worried aunt, who had been searching for her. Together, they embark on a journey to help Souta return.

At her childhood home, Suzume finds the door and enters the Ever-after for the first time since her youth. She finds Souta, restored to his human form. To bring him back, they revert Daijin and another keystone, Sadaijin, to their original forms, using them to seal the remaining worms. Within the Ever-after, Suzume encounters a younger version of herself, offering comfort and reassurance to the child who had lost her mother. Returning to the present, a world free from the threat of disasters, Suzume reconnects with the friends she made along the way.

Finally, on her way back to school, Suzume's path crosses with Souta's once again.