"Suzume no Tojimari" centers on Suzume Iwato, a 17-year-old girl living in a quiet town in Kyushu, Japan. Her life takes an unexpected turn when she encounters a mysterious young man named Sōta Munakata, who is searching for a peculiar door in the mountains. Intrigued, Suzume follows him and discovers an abandoned door standing alone in the ruins of a hot spring resort. Upon opening it, she unwittingly unleashes a supernatural force that threatens to cause disasters across Japan. The door serves as a gateway to another dimension, and its opening allows a giant, worm-like creature to emerge, capable of triggering earthquakes.

Sōta reveals that he is a "Closer," tasked with sealing these doors to prevent calamities. Suzume, feeling responsible for the chaos, joins him on his journey to close the doors scattered across Japan. As they travel, the duo encounters various characters, including Daijin, a mischievous talking cat who transforms from a stone statue into a living creature. Daijin plays a pivotal role in the story, as its actions influence the doors and the disasters they cause. Suzume and Sōta’s mission becomes increasingly urgent as the disasters grow in scale and frequency.

The narrative delves into themes of loss, resilience, and the interconnectedness of past and present. Suzume’s personal history is revealed to be tied to the doors, as she lost her mother in a natural disaster years earlier. Her journey becomes not only a quest to save Japan but also a path toward healing and understanding her own trauma. Sōta, too, carries his own burdens, and their partnership evolves into a bond of mutual support.

The story’s climax unfolds as Suzume and Sōta confront the final door, which poses the greatest threat. Suzume must make a profound sacrifice to restore balance, demonstrating her growth and determination. The resolution ties together the emotional and supernatural elements of the narrative, offering a poignant conclusion to their journey. The film blends fantasy, adventure, and heartfelt drama, creating a compelling tale of courage and connection.