In The Future Diary, Yukiteru Amano is a quiet middle school student who records every aspect of his daily life in a digital diary on his phone. Feeling like an outsider at school, he frequently converses with his imaginary friends: Deus Ex Machina, the god of time and space, and Mur Mur, Deus' assistant. One day, Yukiteru notices his phone beginning to predict future events. Initially dismissing it as a coincidence, he soon realizes the predictions are accurate. As he starts utilizing this power, he discovers that his classmate Yuno Gasai possesses a similar device. Together, they manage to evade a mysterious pursuer and return home. There, Deus Ex Machina reveals that they, along with ten others, are now participants in a deadly game where the winner will become Deus Ex Machina's successor. With no other option, Yukiteru and Yuno must rely on their Future Diaries to survive and win the brutal competition.