See
http://www.iisg.nl/~landsberger/jq.html
"When Mao died in 1976, Jiang lost the support and major source of justification for her political activities. Hua Guofeng arrested her and the other members of the Gang of Four. I personally always thought that the poster below, made in 1976 and published a year later, was an allegorical way of showing the defeat of Jiang. Monkey (Sun Wukong), the hero of the popular Ming-dynasty novel Journey to the West, stood for the Chinese people, and the White Bone Demon, a devil of the first order, was Jiang Qing. However, when I proposed this theory to veteran designers Ha Qiongwen and Qian Daxin (formerly of the Shanghai People's Arts Publishing House), they were very amused, but insisted this was not the case."