Tang Wan, who suffers from a rare genetic disease, unexpectedly acquires the ability to travel through time and move freely between the modern world and the Kingdom of Tianqi. Every time she travels, she runs into Lu Yuan, the cold and imposing Emperor of Tianqi, who mistakes her for an assassin. At first, the two are constantly at odds, but Tang Wan uses her quick wit to escape danger time and again, bringing a refreshing spark of life to the otherwise dull imperial palace. As they match wits and struggle against each other, Lu Yuan gradually finds himself drawn to this spirited and courageous young woman. Tang Wan, meanwhile, discovers that time travel may be her only chance to find a way to prolong her life. Thus begins a remarkable bond that transcends time and space.