Yu Rang was from the country called Jin in the Spring and Autumn Period. This country was dominated by six prominent families, and Yu worked in turn for the Fan Family, the Jhongsing Family and finally the Jhih Family. He was highly regarded by Jhih Bo, the head of the Jhih.

      Jhao Siangzih, the head of the Jhao family, had an unforgivable past argument with Jhih Bo. So he arranged an alliance with the Han and the Wei families against the Jhih. They defeated the Jhih family, whose lands were cut up, and lastly Jhih Bo's skull was used as a wine container by Jhao Siangzih. Believing, "A valuable man should sacrifice his life for the person who truly knows him," and "A female should dress for the person who adores her," Yu Rang decided to avenge Jhih Bo.

      He changed his name and sneaked in Jhao Siangzih's palace. He got a good opportunity to assassinate Jhao when Jhao was in the toilet. Jut before he started the attack, Jhao was aware of it. Jhao's bodyguards were going to kill him but were stopped by Jhao because Jhao praised Yu for his loyalty to the Jhih family and let Yu leave.

      Yu did not give up. He disguised himself by changing his skin color and his voice; he brushed lacquer on his skin and swallowed coal to damage his vocal cords. People asked Yu why he did not pretend to work for Jhao and find a good chance to kill him? Yu refused this suggestion by saying that if he worked for Jhao, then Jhao would become his new master, and he could never betray his master.

      Yu's second assassination attempt failed again. He was arrested after he scared Jhao's horses on a bridge. Jhao questioned him why he did not avenge his masters prior to Jhih Bo. Yu answered that Jhih highly regarded him and knew his true worth.

      Before Yu was executed by Jhao Siangzih, his final wish was to stab Jhao's clothes as a symbol that he had completed his commitment. Jhao let him to do that. He stabbed the clothes three times then committed suicide. The sia in the country all cried for him when they heard this sad news.

      Cihke, the assassins, were the sia who took missions to kill someone mostly for political reasons but not for money. Yu Rang's story is one of the five stories written in the Shi Ji. However, according to the book, Cian Fu Lun, by Wang Fu of the Eastern Han Dynasty, there was an organized group killing people for money in the capital. This group was a disgrace, and its members can not be regarded as sia.