In 1561, nineteen-year-old Mary, Queen of Scots, Catholic Queen of Scotland, returns to her home country from France following the death of her husband, Francis II of France, to take up her throne, where she is received by her half brother, the James Stewart, 1st Earl of Moray. In neighbouring England, her cousin, twenty-eight-year-old Elizabeth I of England is Protestant Queen of England — unmarried, childless, and threatened by Mary's potential claim to her throne. Mary soon clashes with the cleric John Knox and dismisses him from her court. Knox is a protestant and leader of the Scottish Reformation and perceives Mary to be a danger to the kingdom's Protestant supremacy.