Before the Cultural Revolution, in the years 1958–1966, theatre became part of the struggles in the political arena as plays were used to criticize or support particular members of the party leadership. An opera by Wu Han, "Hai Rui Dismissed from Office", was interpreted as a veiled criticism of Mao. It elicited an attack by Yao Wenyuan on the opera, and the attack is often considered the opening shot of the Cultural Revolution. It led to the persecution and death of its writer Wu Han, as well as others involved in theater, such as Tian Han, Sun Weishi, and Zhou Xinfang.