The Crown’s Olivia Colman reveals Netflix show left her ‘obsessed’ with how we ‘never know what the Queen is thinking’

while filming season three of the big budget epic, she said of Her Majesty: "A person made a vow in their 20s to serve their nation, she's done it, she's now in her 90s.

"She's extraordinary. I've become almost obsessed with her. She's amazing."

And the Broadchurch actress, who takes over from Claire Foy to play Queen Elizabeth II, went on to explain how intrigued she is that the nation's figurehead never betrays her emotions.

"She's a rock for the nation," Olivia said. "Her training is to be stoic and strong. You never see what she's thinking, which is eternally fascinating."

The national treasure also explained how lucky she feels getting to film at places where Royal events actually occurred.

The scenes that recreate Prince Charles' investiture, for example, were shot at Caernarfon Castle, where the event took place in July 1969.

"We get to see the most amazing places and inside the most extraordinary houses," Olivia said.

"The public aren't there so you get to ask the experts 'What's that?' We have a lovely time."

Olivia was joined in the interview by Outlander actor Tobias Menzies, who takes over the role of Prince Philip from Matt Smith.

"The show is as much an investigation of the institution as it is of the people, Tobias outlined. "The pressures, the weird loneliness of it and what happens to a family within those strictures.

"Hopefully this breathes life into it and what's going on inside these people."

• Season Three of The Crown is available on Netflix from 17 November