Matteo Ricci arrives in China at the end of the 16th century as the first European Jesuit granted entry, carrying training in geometry and algebra that turns out to matter more than his theology. The film traces how Ricci and two later Jesuits discovered that timekeeping and cosmology sat at the center of Chinese imperial legitimacy, tied to the Emperor's Mandate of Heaven, and how mastering the calendar became a route to influence inside the Forbidden City. Dramatic historical recreations carry the century-long story of astronomical contests between Jesuit scientists and Chinese court astronomers, while modern science historians and time scientists explain what was actually at stake in predicting eclipses and fixing the calendar correctly. The film cuts between this 16th and 17th century power struggle and present-day time labs and satellite systems, drawing out the parallel between imperial calendar authority and today's contest over precise time and satellite data. The result is a history of science story built around a genuine political stake: whoever controlled time controlled heaven's favor.