Lu Renjia, an intern teacher, joins Onion Academy. On the day of her employment, her childhood friend and elder brother, Wu Qi, suddenly goes missing. While searching for Wu Qi, she gradually discovers another soul residing in her body... Who are they? And who am I? As she unravels the mystery of herself, she is fortunate to have companions from the academy fighting alongside her, confronting conspiracies, and revealing cruel hidden truths.