It is said that he won the favour of Duke Ling 晉靈公 (r. 621-607) because of his flattery. Under the reign of Duke Jing 晉景公 (r. 600-581), he was appointed Minister of Justice (sikou 司寇). Tu'an Gu was at odds with the family Zhao 趙 and therefore slandered Zhao Shuo 趙朔 (Zhao Zhuangzi 趙莊子), Zhao Kuo 趙括 and Zhao Tong 趙同, so that the Duke ordered the exintinction of the house of Zhao. Solely an unborn son of Zhao Shuo, Zhao Wu 趙武 (Zhao Wenzi 趙文子), survived and was hidden inside the ducal palace.
In 583, Tu'an Gu was killed by Han Jue 韓厥 (Han Xianzi 韓獻子) and Zhao Wu, and his family was extirpated.
The story of the survival of Zhao Wu has later become a subject of a novella, Zhaoshi gu'er 趙氏孤兒 "The orphan of the family Zhao". In the history Shiji 史記, the assassination of the family Zhao and the survival of the single orphan is recorded for the year 583. Yet many later scholars doubted the authenticity of this story because it is the only story in the Shiji that is not derived from chapters in the histories Zuozhuan 左傳 or Guoyu 國語. Some scholars even doubt that the person Tu'an Gu really existed.