Season Four of Reign started its run on February 10th, 2017 for sixteen episodes, and aired on The CW and E! Canada. It concluded on June 16 with the series finale.
Queen Mary, unsure who to trust, tests her brother James to ensure his loyalty after hearing of his meeting with John Knox. Lord Darnley agrees to help Queen Elizabeth, in an attempt to sabotage the powerful suitor's relationship with Mary.
Queen Mary discovers there is a leak amongst her advisors and sets out to uncover the traitor. Queen Elizabeth enlists in Narcisse to further her quest for supremacy. Meanwhile, Catherine takes desperate measures to regain some of the power she has lost.
Gideon shows Mary what life could be like if she chose love over country. Catherine fights to cover King Charles' increasingly erratic behavior, while Claude finds an enemy in her sister Leeza.
When Lord Darnley surprises Mary with a visit in Scotland, Mary sees a glimmer of a union that could be more than just political. Elizabeth fights to gain allies in her favor and Catherine must work to get Claude back on track by finding her a new husband.
In order to get Mary to agree to a marriage, Lord Darnley must demonstrate his loyalty when she voices her concerns about his true intentions. Catherine and Narcisse work to repair King Charles' reputation after rumors spread about his strange behavior and threaten the throne.
Queen Mary must deal with the political repercussions of a potential marriage to Lord Darnley and King Charles disappears, leaving Queen Catherine to pick up the pieces. Queen Elizabeth comes to Gideon's aid, while Princess Claude receives an interesting proposition.
When Darnley gets a surprise visitor, his marriage to Mary hangs in the balance. Elizabeth learns her attempt to stop Mary backfired. Meanwhile, Catherine and Narcisse find King Charles and must convince him to return to the castle.
As Mary's upcoming wedding looms, a terrible tragedy pushes Mary and Darnley apart, forcing Mary to enlist in Catherine's help. Elizabeth encounters a traitor to Spain, who petitions her to support an expedition to the New World.
Mary and Darnley wed in a lavish affair, which proves to be a successful decision in regards to her political standing. James makes an interesting discovery about Greer, while Elizabeth frantically tries to salvage England's power.
As Mary strategizes ways to take over the English throne, Elizabeth struggles to find an appropriate suitor to marry. Meanwhile, James gets caught up in a scheme orchestrated by John Knox and has to deal with the tragic aftermath.
Mary and Darnley are at odds as they put their plan to seize England into action. Elizabeth is conflicted about her feelings for Gideon as she attempts to find a Catholic to marry. Catherine's son Henri attempts to claim the throne from Charles with the support of Spain and Narcisse.
After a tragic earthquake hits Scotland, Mary must face John Knox amidst claims that she isn't coming to the aid of her people. Elizabeth takes drastic measures after she is discovered with Gideon, while Charles makes a decision that backfires.
Darnley teams up with John Knox to strip Mary of her throne, which will leave a close friend of Mary's dead. Elizabeth must banish Gideon from court at the request of her future husband, while Charles takes a bold stance against his brother Henri.
Mary pursues her quest for justice as she launches a counter attack on her conspirators. Elizabeth suffers a major setback that turns her world upside down.
Childbirth threatens to take Mary's life, which leaves her and her unborn child's safety in jeopardy. Elizabeth discovers that someone in her inner circle was the cause of the death of someone close to her.
Mary makes a decision that will change the course of history -- forever shaping the fate of her nation, her crown, and her newborn son. Mary's perilous move for her survival causes the stunning realization that perhaps she is not the only one who may not survive. Meanwhile, Elizabeth steadies herself for war and will become the instigator in Mary's demise while later realizing she and Mary might be more similar than either thought.
Premise
The fourth and final season, opening in the early 1560s and ending in 1587, has Queen Mary returned to Scotland as its rightful ruler and trying to regain power in her homeland. She has to manage her allies, such as her bastard older half-brother James Stuart and the outspoken Lord Bothwell, as well as her enemies such as the Protestant preacher John Knox. Tensions mount between Queen Mary and her own cousin Queen Elizabeth, with Queen Mary marrying Lord Darnley, an English Catholic claimant to the English throne, in the hopes of taking England. In France, Catherine has to protect her mentally damaged son, King Charles, from the ambitions of her eldest daughter Queen Leeza of Spain, and their cunning teenage youngest brother, Crown Prince Henri.
