The 42-year-old director relished working with the Hollywood stars on the drama movie – in which Saoirse plays Mary Stuart and Margot plays Queen Elizabeth I – and she thinks they were the perfect foils for one another.
She explained: "Saoirse and Margot really inhabit their roles and that’s exciting to me. They are incredibly intelligent woman but they’re also very physical creatures, and they complement each other’s energy.
"Mary and Elizabeth are two sides of the same coin. There’s a magnetic thing going on – they attract and repel. That’s always a powerful energy if you can get that right on screen – and I think they have it."
The movie isn’t entirely consistent with real-life events, but Josie insisted she hasn’t overly dramatised the challenges facing the two queens in their male-dominated environments.
The director – who is best-known for her theatre work – told Den of Geek: "They faced gigantic odds, not only in improving their legitimacy to be the ruler of their countries, but also their legitimacy to hold that place as a woman.
"It’s certainly the case that this was a period of history where many people thought it was against nature for women to lead … I’m not sure that’s totally bled out of our culture just yet."