Rintarou Okabe, the self-proclaimed mad scientist notorious for his eccentricity, has fallen into profound despair after failing to save Makise Kurisu. Now depressed and withdrawn, he abandons his scientific pursuits to live as an ordinary college student, attempting to flee the haunting memories of his time-traveling adventures, which remain a secret to everyone around him. While working as a receptionist at a technology conference, Okabe meets Maho Hiyajo, an energetic young woman who later provides translation for a lecture by Professor Alexis Leskinen. During the event, Alexis and Maho introduce Amadeus, an advanced artificial intelligence capable of replicating a person's memories, personality, and behaviors with extraordinary precision. Following the lecture, Okabe learns that Maho and Alexis were former classmates of Kurisu and have created a digital recreation of her. Tasked by Alexis with observing the AI's actions, Okabe is given the chance to interact with a digital version of his deceased friend. Caught in a dangerous confrontation with his past, Okabe must face painful truths and navigate the consequences of interfering with the natural flow of events.