Future Diary follows Yukiteru "Yuki" Amano, a socially awkward boy and one of the game's contestants who only wants to survive; Yuno Gasai, another one of the game's contestants and a friend, who would do anything to be with Yuki; Minene Uryū, another contestant who is an infamous spy with a grudge against God; and Aru Akise, a genius teen detective and a friend of Yuki who investigates the true purpose of the game and Yuno's dark secrets.
The first opening and ending theme songs are "Kūsō Mesorogī" (空想メソロギヰ, "Fantasy Mythology") by Yousei Teikoku and "Blood-teller" by Faylan, respectively, which aired from episode 1 to 14.
All episode titles are terms related to modern cellphones and telephone business in general, reflecting the fact that most Future Diaries are based on their users' mobile phones.
In the present, Aru challenges Hinata to guess which hand he is hiding a coin in, with his diary as the forfeit.
Yuki, Yuno, Aru and Kosaka leave the park, while Hinata uses her diary to send the dog pack after them.