The Clouds Over the Founding of the Tang Dynasty

Xie Xuan, a history student at Peking University, accidentally touched half of a stone disc at an archaeological site and unexpectedly transmigrated to the Tang Dynasty, during the Tianbao era. Through a twist of fate, he met Zhang Jiuling, the celebrated chancellor of the Kaiyuan era, who should have died long ago. Impressed by Xie Xuan, Zhang helped him enter officialdom. At a turning point when the Tang Dynasty was shifting from prosperity to decline, can Xie Xuan, armed with his knowledge of history, turn the tide?