The Tenth Doctor, Rose, and Mickey explore a derelict spaceship in the 51st century. The Doctor looks through a time window, a doorway to another place in space and time, which is shaped like a French fireplace. He sees a young girl called Reinette on the other side of the fireplace who is in 18th-century Paris. The Doctor steps through the time window to find that months have passed. He discovers a clockwork service android disguised in 18th-century clothing hiding in Reinette's bedroom, and saves Reinette from it. The Doctor discovers a horse that stepped through a time window; he names it Arthur. Returning to Reinette's bedroom, the Doctor discovers that she is now a young woman. Reinette and the Doctor kiss before she leaves to join her mother. The Doctor realises Reinette is Madame de Pompadour, the mistress of King Louis XV.