Wu had her fourth and youngest son Li Dan crowned as Emperor Ruizong, but in fact maintained total rule. The young boy was not moved to the emperor’s chambers, nor appeared at any public function. He was essentially a prisoner in his private quarters. Wu stopped speaking from behind a screen or showing other outward signs of deference to the male gender.
As Empress Regent, Wu installed copper boxes around the imperial city where residents could anonymously tattle on one another, and developed a highly effective secret police. In 690 she had Ruizong give up his nominal rule officially, declaring herself leader of a new Zhou dynasty. The 690s were a reign of terror for high ranking Chinese officials and she ordered at least 30 suicides during the decade.
By this time Wu had the official title of Empress Regnant but styled herself as “emperor” or “female emperor”. She carried on an affair with a Buddhist monk and elevated the Buddhist religion, building temples in each prefecture. Wu initially named Li Dan as her successor, though for a time contemplated naming a member of the Wu clan as heir.
Wu had a great number of people executed during her reign, almost all of them perceived threats to her rule. When she ordered the execution of Li Dan’s wife and mother in law for witchcraft, he was too fearful to speak up for them or even mention them after their deaths. She barred her ministers from meeting with Li Dan and had him investigated for treason.
As his servants were being tortured to give false confession, one attested to Li Dan’s innocence so fervently he slit his own belly to show the fortitude of his conviction. Wu had the servant sent to surgery to be saved, and called for an end into the investigation on Li Dan.
In 694 Wu became briefly enchanted with various forms of mysticism. She claimed to be the future Buddha to gathered support for her rule. However, in 695 when these mystics failed to predict a fire set by her jealous Buddhist monk lover, Wu became skeptical and enraged. She had her mystics demoted to slaves.