Shen Qingya, the youngest memory purifier of the Dayin Dynasty, was born with the eye of peeping into memories, and specialized in erasing memories that the royal family should not keep. While cleaning the memory of the seventh prince, he unexpectedly saw the afterimage of the founding prince Yin Chengji who was accused of treason a hundred years ago. As memories related to the forbidden prince continue to appear in the palace, the Forgotten Potion has a hidden effect of enchanting the soul, and successive memory washers die mysteriously and suddenly, Shen Qingya gradually discovers: What he erases is never a stain, but the centuries-old truth that has been deliberately buried.
