Watch HDToday. In China's Valley of the Kings, there stands a tall, carved stone. It honors the resting place of a woman named Wu Zetian, who rose from concubine to become China's only female emperor. For more than a millennia, history claimed she killed her own children, held power through a ruthless rule of terror, and brought China to the edge of ruin. But are any of these claims true? Join the investigation as we revisit old evidence and reveal new truths, using artifacts and forensic tools to tell the true story of China's Emperor of Evil.