Zhu Ling was born in Beijing, in 1992 she was admitted to Tsinghua University. The Zhu Ling event (朱令事件) refers to the bizarre case of thallium poisoning. In 1995, the police accepted the case of thallium poisoning, which as identified as poisoning incident. After investigation, however, the case had its ups and downs, the murderer is still not known. In April 2013, with the happening of the Fudan poisoning case, the voice for a thorough investigation into the case of Zhu Ling had also re-emerged, the former crime suspects SUN Wei was in widespread controversy in the public.