At the court of Charles II, young John Churchill advances his career by serving the king’s bastard son, Monmouth, in the field of battle, and by bedding the king’s mistress, the Duchess of Cleveland. Young Sarah Jennings is also advancing at court, by befriending the king’s sister-in-law, the Duchess of York, and teaching the York princesses, Mary and Anne, the art of gambling. At a court masque, the two meet, and sparks fly. (thetvdb.com)