Watch: Duke and Duchess of Cambridge speak to Emma Stone and Emma Thompson about Cruella
Prince William joked he should have had actor Emma Stone "stopped" for riding a motorcycle outside Buckingham Palace during the filming of the movie Cruella.
William and his wife Kate spoke to Hollywood stars Stone and Emma Thompson ahead of the release of their new movie, which tells the origin story of Cruella, the villain of 101 Dalmatians.
Kate asked the actors if the film had been fun to shoot, to which Stone replied: "It was so much fun, we were all over London, in front of Liberty.
"They transformed Carnaby Street into 70s London, which was amazing.
"We were in front of Buckingham Palace at one point, I was riding a motorcycle around The Mall."
William replied: "We should have had you stopped. It's very dangerous."
Stone laughed and said she "really got away with it".
The two actors also shared their love of the costumes in the film, with Thompson joking that she thought they had been sourced from her own wardrobe.
"I was alive in the 70s so I kept looking at all the frocks and saying I think that's mine... I'm sure I wore that, you won't remember because you are all too young!" Thompson said.
She also recounted one occasion when they had to take the tube instead of driving through London because of a protest being held in the capital.
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Despite a "rammed" underground and her elaborate costume at 9am on a Sunday, Thompson said "no one batted an eyelid".
William also shared more about a "flirty" moment he shared with a woman in her 90s, which happened when he visited a care home on Sunday.
He said: "I got propositioned by a 96-year-old lady called Betty yesterday who wanted to kiss me.
"She's in a care home with her daughter and I said: 'Betty if I do that I'll get slapped on the back of the head for inappropriate social distancing,' and she said 'I'll have you afterwards then'.
"She was a right character."
Kate said: "This is what happens when I'm not around!"
Thompson called the royals "darlings" as she excitedly talked about the work of the NHS during the pandemic.
Kate said some of the workers told her they felt guilty when they contracted COVID-19 for leaving their colleagues continuing to face the challenges on the frontline.
The Duke and Duchess of Cambridge, who are the Earl and Countess of Strathearn when they are in Scotland, hosted a drive-in cinema for NHS workers, showing Cruella two days before it is released in the UK.
The duchess gave a short speech thanking them for their hard work and encouraging them to "cuddle up" and enjoy the film.
Then she joined her husband in a Land Rover that had belonged to the Duke of Edinburgh, which they borrowed with permission from the Queen.