In I am a Witness, he is Tang Zheng, the first hero of the villain, and Tang Zheng's sister's face is hurt. In Tang Zheng's memory, her sister always came home late and always used it? Just about? This software dates other men. Once, when he saw his sister's face hurt, he got angry, and then taught her a lesson, but accidentally killed her.

Later, Tang Zheng began to take revenge on others because of her sister's death. He used it? Just about? The software asked young girls out, then knocked them out, and finally turned them into his sister. When the police investigated Tang Zheng, they found the girls imprisoned by Tang Zheng, who were all transformed into her sister by Tang Zheng.

Tang Zheng used to be a great young man with a good job. He is a cosmetic doctor. Because he killed his sister by mistake, his psychology began to distort, and he finally chose to retaliate against society.

Tang Zheng is a pervert. When he met Lu Xiaoxing, he found that Lu Xiaoxing's experience was similar to his. Under the report of Lu Xiaoxing, Tang Zheng's crimes began to be exposed, and finally Tang Zheng chose to kill Xiaoxing. Fortunately, with the help of Lin Chong, Xiaoxing was saved, and Tang Zheng was finally punished by law.