As Reign Season 3 Episode 6 begins, Bash and Charles ride into the castle. Bash offers his counsel as brother to young Charles, who will soon be king. Lord Grenier, a member of the privy council, offers to take Charles hunting, but Bash advises against it. Charles goes anyway, lured in by the promise of a Greyhound dog. Bash fears Lord Grenier will not support Catherine in the quest for the Regency.
Greer helps Mary as she packs away Francis' things and is moved to a lesser room in the castle. Bash visits Mary to enlist her in speaking to Catherine, who is mired up in her grief and cannot bother herself with the happenings in the privy council.
Sir Nicholas takes the news that Mary destroyed the treaty to Elizabeth who vows to send troops to Mary's birthplace immediately. She also begins scheming to get Lord Dudley back into the castle by offering his wife a position at court, Keeper of Swans.
Catherine and Mary burst into the privy council's meeting to find out why they're meeting without an elected Regent. Catherine wants to give up the fight against them, but Mary vows to fight the nobles for her in order to fulfill her promise to Francis.
Lola and Narcisse discuss Lola's anxiety about Catherine and he begins discussing fantasies with her. He would like her to be more aggressive, but she feels demeaned by his suggestion.
Greer and Mary learn that Elizabeth has taken their birthplace without a fight, but Mary believes there's nothing she can do. Greer tells her that it's time she consider a suitor and an alliance in order to save their home from Elizabeth, which turns Mary's attention toward Spain.
Claude calls for Leith to arrange a carriage to take her into the village, but her real reason for having him there is so she can suggest a relationship between him and a girl just above his station. She has feelings for him but wants to see him married better than he was born.
Charles finds Mary in his study looking through Francis' old ledgers. He tells her that he wants his mother as Regent and doesn't trust Grenier, but he doesn't know how to defeat the nobles.
Dudley returns to Elizabeth to confront her about the job she gave his wife. Elizabeth vows never to marry if she can't have Dudley and they end up sleeping together. Again. He returns to his chambers to find Amy there alone. He suggests they do not discuss Elizabeth.
Greer and Mary learn that Lord Grenier and his wife are in a sexless marriage and Mary deduces it may be because his wife loved another woman, the Duchess of Anjou. Mary suggests one of Greer's employees might be able to get the information they need to stop Lord Grenier from becoming Regent.
A doctor diagnoses Amy with melancholia and blames it on the fact that she and her husband do not have sex. She seduces the doctor so that he'll diagnose Amy with a mass instead so that Dudley's affections will return to her. His course of treatment involves a sojourn in Cornwall with a physician there, which will take Dudley away from Elizabeth.
Claude tries to teach Leith the ways of the highborn, which includes dancing and dining. Instead, he ends up teaching her dances from the village.
Dudley breaks the news to Elizabeth that he must go to Cornwall with his wife, which means their dalliance must end. Elizabeth believes Amy's illness is fate's way of telling them they can be together, but Amy has to die first.
Catherine and Mary visit Lord Grenier to tell him they know about the emergency vote and about the ways he's been amassing his fortune by profiting off the soliders who have died in the war against England. Catherine knows that if she is Regent, she will have to withdraw the troops from Scotland, but her heart tells her the troops must stay. Mary knows that helping Catherine win might jeopardize Scotland.
Mary announces in front of the privy council that she relieves France and her armies of their duties to Scotland. Elizabeth learns the news of France's retreat and Sir Nicholas suggests now would be a good time for Elizabeth to abandon her fight against Mary. She decides to replace him as her ambassador to France instead.
Catherine walks in on Narcisse as he's dressing to tell him that she plans to ruin his life with Lola once she's Regent. He reveals that he has a seat on the privy council and will cast the deciding vote. She ensures his vote will go to her.
Claude tries to continue her plan to teach Leith the ways of the nobles but he knows there is no Juliet. She just wanted to spend time with him because she wishes they could be together.
Elizabeth sends one of her prisoners to France to make Mary fall in love with him so that she can thwart her attempts at an alliance with Spain. Charles suggests to Mary that she seek a new suitor there, in France, so that Spain will see that she comes with more than just a war-torn country.