Along with three others, Natsu wakes up without an idea of what has happened; the quartet reaches an island to try to figure out a way to survive.
Convinced that Botan has kidnapped them, Natsu and Arashi sneak out of camp and run into another survivor; Botan reveals what she knows.
Natsu's clumsiness indirectly leads Team Summer B to the rest of the group; her memories help them figure out their location -- and their next moves.
Arashi, Natsu and Semimaru stumble on the Team Autumn settlement in the former Kobe region; they seem to be thriving, but their leaders are tyrants.
In the ruins of Tokyo, Natsu, Arashi and Semimaru meet Team Winter's sole survivor; Team Spring reaches Mount Ogino Fuji and finds Natsu's message.
Aramaki joins Team Spring, despite Fujiko having doubts; Hana decides to search for Arashi after hearing that Aramaki met someone who fits his description.
東山奈央
Natsu Iwashimizu
福山潤
Arashi Aota
小西克幸
Semimaru Asai
沢海陽子
Botan Saotome
阿澄佳奈
Matsuri Tendo