Three moments in Takaki's life: his relationship with Akari and their forced separation; his friendship with Kanae, who is secretly in love with him; the demands and disappointments of adulthood, an unhappy life in a cold city.

Aya Okamura has been working for two years and has begun living on her own for a job opportunity. With her mother working overseas as a doctor, her father is now living alone with the family's longtime pet cat Mii-san. One night, Aya returns from a long day at work, and as she rests on her bed, she reminiscences about the times the family had together. She remembers the sadness she felt when her mom went overseas, and the solace she felt when her father brought home Mii-san to give her comfort. Then, she receives a phone call.

In the future, the Japanese government captures a class of ninth-grade students and forces them to kill each other under the revolutionary "Battle Royale" act.

Takashi and four of his classmates, fourth-grade students, cannot succeed in doing a back pullover around a horizontal bar. Their gym teacher warns them: they have one week to succeed; if they resign now, then, tomorrow, facing life difficulties, they will always run away and become bums.

An apocalyptic look at the possibility of an earthquake of magnitude 7 or greater striking the Tokyo area. Mirai, a middle school freshman girl who goes to Tokyo's artificial Odaiba Island for a robot exhibition with her brother Yutaka at the start of summer vacation. A powerful tremor emanates from an ocean trench, the famed Tokyo Tower and Rainbow Bridge crumble and fall, and the landscape of Tokyo changes in an instant. With the help of a motorcycle delivery woman named Mari who they meet on Odaiba, Mirai and Yutaka strive to head back to their Setagaya home in western Tokyo.