The Doctor, Rose and Mickey travel to what appears to be an abandoned space ship in the 51st century. The engines are functioning however and the power is being used to power a portal to 18th century Paris. There the Doctor meets a young girl, Reinette and saves her from a creature under her bed. He sees again her after some years have passed and as a young woman, she is the future Madame de Pompadour. He soon realizes that the ship has been geared to track her activities at various points in her life but it's not exactly obvious why they are doing so. At the same time, he and Reinette develop a unique bond.
—garykmcd