Princess Li Lizhi of Chang Le from the Great Tang accidentally travels a thousand years into the future while trying on her wedding dress, landing in the home of a modern young man named Ling Yuan. Meanwhile, a mysterious celestial screen appears above the Taiji Hall during the Zhenguan era, livestreaming the princess's modern-day experiences in their entirety. Intelligent devices and ingenious ways to beat the heat continually overturn the Tang people's understanding of the world, while the future fate of the Tang Dynasty leaves the entire imperial court deeply unsettled. With a five-day pact between two eras, what surprises and shocks lie hidden in this encounter spanning a thousand years?