Quiet ballet student Choi Jiwoo lives by one rule: never let anyone see who she really is. At Haneul High, she's quiet, guarded, and forgettable. By night, she's MG-an anonymous investigator exposing the city's darkest secrets from behind a screen. Keeping those two lives separate has never been difficult. Until Ye-on, the only person she's ever let close, becomes the target of relentless bullying... and a boy from the neighboring Daehan High starts seeing through the walls she's spent years building. The closer the truth gets, the harder it becomes to decide which version of herself is real.