One of the most shocking scenes in the upcoming Mary Queen of Scots movie comes when Mary Stuart, played by Saoirse Ronan, walks in on her husband Henry Stuart, Lord Darnley in bed with her gay male courtesan, David Rizzio, on her wedding night in 1565.
The movie takes some liberties with historical accuracy — Mary and Queen Elizabeth I (Margot Robbie) never met as their faceoff scene suggests — but historian John Guy, whose book Queen of Scots: The True Story of Mary Stuart serves as the historical basis for the film, assures the Henry (Jack Lowden) and Rizzio (Ismal Cruz Cordova) connection isn’t one of them.
“Darnley and Rizzio having a sexual relationship is definitely true to history,” Guy tells PEOPLE in this week’s issue.
In the historical drama, Mary, who hoped to take the English throne and bring both countries under one rule again, wasn’t concerned with her husband’s relationships with men because he helped her produce a male heir, their son James.
“It was a very smart match in terms of making her claim to the English throne even stronger,” director Josie Rourke says. “There is a reason that James I was the first monarch to rule both kingdoms and that’s because Mary Queen of Scots was smart enough to have a child with Henry, Lord Darnley. Darnley also had a claim to the English throne, so that massively strengthened Mary’s own plan and the plan of any children that she bore by him.”
Ronan, 24, echoes that Mary knew what she was doing when she got pregnant — but probably would’ve also liked to be in a fulfilling marriage.
“She was painted as this silly little girl and she really wasn’t,” the Irish actress says. “She led with her heart and she just wanted to be in love.”
When Henry assisted Mary’s council in killing Rizzio, one of Mary’s close friends, as part of a larger plan to take her crown, Mary grasped that she must protect herself and her son.
“Their relationship is completely fractured,” Rouke says. “Mary realized because of all the betrayals that she’s suffered, she has to look forward and rely on her own power and her own strength, rather than outwards to the man she’s married.”
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Henry didn’t ultimately go through with any of the schemes to steal power from his wife, and because of his unwillingness to comply, Mary’s advisors banished him and eventually had Henry murdered in 1567.
“As soon as he gets married to her, he started to try to undermine her,” Rourke says. “He wanted to be named king alongside her and take her power. Really that was his father who was behind that. The issue was that Darnley was too weak to be able to make and carry off the ambitious move. So he had the appetite but not the stomach for it.”
Mary Queen of Scots hits theaters on Friday.