Detective Akechi in a frenzy.

The manga's story is an homage to Edogawa Rampo's The Boy Detectives Club novel series. The mystery centers around Mayumi Hanazaki, a middle-school girl who used to live with her aunt and uncle until a mysterious person mercilessly killed both. Now, thanks to an unusual incident, Mayumi relies upon the spirit of the legendary detective Kogoro Akechi to solve cases.

In a parallel world where the strongest of the non-diary holders "Akise Aru" takes the place of Yukiteru (the protagonist from Mirai Nikki) for a few days, what will happen?

Find out more about the other characters from Mirai Nikki - Future Diary. These stories start out a few days prior to them receiving their own diary and give us some insight as to how they think and their personal reasons for using the diary they've been chosen to have. In the process learn a little more about Deus ex Machina, the 'God' of Space and Time, and what his goal really is.

Second-year high schooler Amano Yukiteru is a boy who has problem making friends. He thinks of himself as a bystander and will always write down everything he sees in a cell phone diary. Tormented by solitude, Yukiteru began to imagine things like a friend called Deus Ex Machina who is apparently the Lord of Time & Space. Seeing Yukiteru's miserable state, Deus gives him a new ability - his diary will now record events that will happen in the near future. Yukiteru is then forced to participate in a game which the winner will become Deus's successor. Now a vicious game of survival is about to begin among twelve future diaryholders - with the winner crowned god of the new world!

The manga's story centers on an introverted high school student named Eiji Hoshimiya with a huge secret — he wished for the destruction of the world when he was younger. Fairies give certain people special powers called Orders. What Order Users can do with their power depends on their wishes. 10 years after the Great Destruction, Eiji struggles to come to terms with his immense power.