Subarashiki Hibi is a story told in six chapters. The chapters are of varying lengths and structure, but for the most part, they cover the month of July 2012 from a number of different perspectives.
The story begins in chapter #1, ‘Down the Rabbit-Hole” on July 12, 2012. The protagonist; Minakami Yuki; lives a peaceful everyday life with Tsukasa and Kagami; her childhood friends; when one day she meets a mysterious girl, Takashima Zakuro (a girl in another class in Yuki’s school, who seems to have met Yuki before but Yuki does not remember this).
The next day, she learns that Takashima Zakuro has killed herself. Rumours in school are abuzz about predictions of the end of the world in 2012 – one of which is a Web site called the “Web Bot Project”, a network of crawlers designed to harness the ‘collective unconsciousness’ to make predictions.
A boy in Yuki’s class named Mamiya Takuji stands up and makes an apocalyptic prediction, stating that the world will end on the 20th, that Zakuro’s death was the first sign. He speaks of an event he dubs “the Last Sky”, where the world will be destroyed and reborn.
The clock is ticking and more people die as the prophesied date draws closer and closer while Yuki attempts to get to the bottom of the identity of Mamiya Takuji, the Web Bot Project and the Last Sky.