Si Si, a modern orphan, inherits a struggling commercial tower and is hounded by loan sharks. When two adorable children accidentally activate a portal connecting the past and present, she uses modern food supplies, iodized salt, and running water to relieve the famine, plague, and water shortage in Qi, an ancient kingdom, and its city of Qiushui. Prince Rong, the war god Qi Mohan, repays her with antiques, calligraphy, and paintings, making her rich overnight. A tyrannical emperor grows wary and sends 300,000 troops to the border. Si Si provides bulletproof vests and grenades, helping the prince turn the tide against overwhelming odds. With the children bringing them together, the two gradually fall in love and save each other across time, joining forces against enemies in both the modern and ancient worlds.