Speaking to ODEntertainment alongside her co-star Josh O’Connor, Corrin revealed she had taken one of Diana’s replica necklaces from the set.
“So the scene we were doing was in Diana’s room or something, and there was just like loads of jewellery in a jewellery box and there was a gold chain,” she said.
“So I stole the gold chain, which I wear.”
Though the chain was fake, O’Connor, who currently plays Prince Charles on the series, joked that it was an “absolute outrage” that she had stolen the real thing.
“It came from the V&A and she’s nicked it and everyone’s looking for it!” he laughed.
As well as Corrin and O’Connor, The Crown’s fourth season will also see Gillian Anderson star as Thatcher, alongside returning cast-members Olivia Colman, who plays Queen Elizabeth II and Tobias Menzies, who plays Prince Phillip.
Helena Bonham Carter will also reprise her third season role of Princess Margaret, Countess of Snowden.
The show this week debuted its first trailer for the new season, which will be released on Netflix on 15 November.