The Crown star reveals Prince Charles ad lib which didn't make the cut

That’s according to Josh O’Connor, the actor who plays Prince Charles in the regal drama. Speaking to Town and Country, the star revealed one extra got carried away in an episode devoted to Charles and Diana’s 1983 tour of Australia.

Addressing a crowd waiting for Diana (Emma Corrin), O'Connor told the audience, “She’s busy working, I’m afraid. You’ll just have to put up with me.” Although only directed to ask about the Princess’ whereabouts, one extra ab-libbed, to everyone’s surprise, “But you’re rubbish.”

Unfortunately, RadioTimes.com understands that the cheeky improvisation isn’t audible in the show’s final cut.

In the same interview, Corrin (who is set to make her debut on the show) revealed it took eight months of talks before she was offered the part of Diana. “It was the most exciting proposal I’ll probably ever receive in my life,” she said about finally being cast.

The star also opened up about the further six months she took preparing for the role, studying the Princess' stance and speech in particular. “No matter what Diana is saying, it kind of goes down at the end,” Corrin said. “It’s like a sadness.”

Corrin explained how she interpreted Diana’s struggles assimilating with Charles’ family. “The coldness, the traditions, and the expectations of behaviour…I don’t think she expected that,” she said. “I think she expected to join a family.”

This alleged coldness from the royals, Corrin claims, was perfectly embodied by Olivia Coleman (who plays Queen Elizabeth II). But only when the cameras started rolling.

"Obviously, Olivia is the biggest ray of sunshine ever,” Corrin said, adding how once director Ben Caron called for action Coleman would instantly change. “She just went stone-cold horrible […] It was so hard to not take it personally.”

Series four is set to arrive on Netflix in November, covering the events from 1977 up to around 1990 with Corrin and Gillian Anderson (as Margaret Thatcher) making their debut on the show.

The upcoming series will be the last outing for all the current cast as their characters, with a new intake of stars taking over the roles. These include Imelda Staunton (Queen Elizabeth II), Lesley Manville (Princess Margaret), Jonathan Pryce (Prince Philip) and Elizabeth Debicki (Princess Diana).

The Crown season four will be released on 15th November 2020 on Netflix. Looking for something else to watch? Check out our guide to the best series on Netflix and best movies on Netflix, or visit our TV Guide.