Elaborate on the synopsis of Gan Long's plot.

The play tells the legendary love story of three folk women that Emperor Qianlong met during his three incognito tours, visiting people's feelings and correcting corruption. It is divided into three units: Thanos in the South of the Yangtze River, Fengyun in the West of Yunnan and Love in the Palace. In order to defend the country and safeguard the peace and prosperity, Emperor Qianlong, as the "Fourth Master", took Cao's adults, Jia, Jia and his party on a private visit, paid attention to people's livelihood, solved people's worries, devoted himself to people's welfare, eliminated corrupt officials and bullies, bent the law to oppress the people, wiped out gangs plotting to rebel and assassinate the emperor, and called on desperate people to be used by the court. Qianlong was a diligent and loving emperor, and also a romantic and affectionate emperor. His lingering love with three strange folk girls with different identities ended in vain and became a much-told story.