In the shadow world without light, Mo Gui is a lurker. He uses musical notes as blades and wanders in the silent darkness. Everyone here hides their own melody, and only Mo Gui can hear those suppressed and distorted voices. His mission is not to assassinate or steal, but to deconstruct the enemy's soul music - in lurking and exploring, he uses music to reshape his identity, weaving lies and truth between the scales. Mo Gui longs to find the lost "original movement", which is said to be able to harmonize the shadows and lights of the world again, but every time he dives in, the melody tempts him to lose himself. The central conflict is that Mo Gui must choose between loyalty to his mission or listening to the song of his heart. If he fails, the shadow world will remain silent forever. The story uses the sense of sound as a clue, the rhythm jumps, and the language flows like a musical score. It is a secret concert about identity, desire and redemption.