Ryouko Otonashi, a lively student at the prestigious Hope's Peak Academy, faces a unique challenge as a chronic amnesiac. To cope, she meticulously documents her experiences in a trustworthy notebook. Supported by her grumpy childhood friend and brilliant neurologist, Yasuke Matsuda, who aims to heal her condition, Ryouko finds solace in their deep bond. Their harmonious routine is disrupted when a mysterious girl embodying despair appears, testing Ryouko's resilience. As secrets unravel and trust falters, Ryouko must decide between holding onto hope amidst uncertainty or succumbing to the shadows of despair.