Lu Yan, a modern social animal, accidentally traveled to the Dajing Dynasty and was regarded as a "little gentleman" by the young emperor Xiao Jingyuan due to some strange combination of circumstances. With modern knowledge, he has always accompanied Xiao Jingyuan with sincerity and wisdom, from interpreting the emperor's thoughts and providing suggestions to quell the southwest rebellion to breaking secular prejudice and becoming the first male queen of Dajing. In the court, he faced the opposition of conservatives and used rail cars and gunpowder bags to help the national economy and people's livelihood; in the market, he implemented water filtration devices and improved public toilets to effectively improve people's lives. From the fearful exploration in the side hall to the side by side on the city tower, Lu Yan not only found a sense of belonging in the strange ancient times, but also joined hands with Xiao Jingyuan to write a vivid chapter of the Dajing Dynasty with love and innovation - here there is the affectionate bond between the emperor and the "sir", the passionate innovation of modern thinking colliding with the ancient system, and the responsibility of protecting the country and the people.