HOW do you respond when you meet the Queen? Well, most people would normally lead with either a bow or curtsy.
But when British actor Riz Ahmed came face-to-face with The Queen, he became so flustered that he actually tried to "spud" Her Majesty - and it's an awkward moment that will haunt him for life.
Recalling the incident on James Corden's The Late Late Show, Riz says his visit to Buckingham Palace in 2018 was "intimidating"... to say the least.
He joked: "There's all these dudes stood around her with scrolls - they're called masters of the scrolls - like some Lord of the Rings business."
After his name was called out to approach the monarch, the actor explained how The Queen extended her hand out to him with her palm facing down.
Although Her Majesty was inviting him to shake her hand, Riz says it was "very unclear what he should do" in response.
To make matters worse, Riz misinterpreted her movement as The Queen trying to "spud" him and went in to reciprocate.
He continued: "All the people around her were like, 'he's going to punch The Queen'."
Luckily, it dawned on Riz at the last minute that the monarch (sadly) wasn't trying to fist bump him.
But in his confusion over what Her Majesty meant, Riz then started stroking her instead.
However, Riz isn't the only A-Lister who has experienced a cringeworthy moment with The Queen.
Last year, we revealed how Madonna broke into fits of giggles after The Queen failed to recognise her on the red carpet.
Meanwhile, Shawn Mendes stood in silence with the Queen for 10 whole minutes after being told he wasn't allowed to speak to her.
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In more Royal Family news, The Queen never eats sandwich crusts and all of her potatoes are the same size.
And Sharon Osbourne has said it's "sad" Meghan Markle and Prince Harry didn't give royal life a "proper shot".
Plus The Queen revealed she "can't look down" while wearing her crown because her "neck would break".