Late at night, the silence of the dark and somber hall of a prison is shattered by a cry of horror. A female inmate Lu is accused of trying to murder another inmate. This caught the attention of Police officer Hao. Hao begins by reviewing Lu's pre-incarceration murder case file. On the surface it appears to be a normal murder case of a wife losing control because of her husband's domestic violence. From her contact with Lu, Hao learns that despite her mild and powerless appearance,
nothing is as it seems. Hao begins to have doubts about Lu's conviction for murder in the first place.

What follows is a complex spider web of veils being lifted one by one, involving Lu's mother's murder of Lu's "stepfather" who supposedly has repeatedly raped Lu when she was five. As we flash back in time, the investigation brings all hidden ghosts up to the surface. Hao discovers that Lu was still a virgin up until when she was in college. She was never raped by her stepfather and her mother is imprisoned for the killing of an innocent man. Hao decides to use deep psychological analysis to help Lu visualize what really happened at her own murder scene, and eventually got Lu acquitted by reason of insanity. Lu, now out of prison, finally sees her mother in prison in after 20 years. Her aged mother tells her the final secret......