The Harbinger of Miracles follows Anaki, a seemingly ordinary seven-year-old boy with an extraordinary burden - he has foreseen the end of the world. After nearly drowning at a summer holiday, Anaki awakens in a reality he believed was behind him, where a mysterious and devastating apocalypse known as "Heaven's Wrath" begins. With his intimate knowledge of the coming destruction, Anaki becomes determined to prevent the tragedies he remembers, saving as many lives as he can - starting with his teacher Miss Yaryu and his classmates Orion and Eli.

When a young boy named Anaki wakes up after nearly drowning, he finds himself back in his childhood and must use his premonitions of a future world-ending apocalypse to rally his friends and protect them from an impending catastrophe known as the Heaven's Wrath.