Plot summary
The ailing Queen Marie de Guise needs help evading the English-backed Protestants in Scotland, so Mary and Francis manipulate Nicholas into giving false intelligence to Elizabeth, ultimately enraging the English queen and saving Queen Marie. Don Carlos of Spain ( Mark Ghanimé ) visits England to court Queen Elizabeth, but is rejected when he demands she disprove a rumour that she's secretly a man. Queen Elizabeth tells Robert her suspicion that Amy is responsible for the rumour; Robert assaults Amy but is quickly remorseful and promises to end his affair with Queen Elizabeth.
Bash tracks down and saves Delphine from being tortured by nuns. Prince Charles, having learned of Delphine's extraordinary abilities in healing, orders her to revive his half-brother, who has died in Queen Mary's arms. Queen Mary agrees to Delphine's price of a life for a life, but when King Francis awakens, Queen Marie de Guise simultaneously dies in Scotland. Queen Catherine figures out that Lord Narcisse tricked Lola into marrying him. Lady Lola is suspicious that Lord Narcisse is still keeping secrets from her.
Credits
Adapted from Wikipedia contributors, Reign season 3. HTML formatting and reference markers removed.