The Queen took the world by surprise on Saturday as she shared afternoon tea with Paddington Bear, starring on screen with her own marmalade sandwiches and lighting up the Platinum Jubilee celebrations as only she can.
The monarch delighted an audience of millions around the world by inviting the animated bear for tea at Windsor Castle in a top secret sequence in honour of the Jubilee.
The sketch was a surprise even to some of her children, grandchildren and great-grandchildren watching in the audience and at home.
Said to have wanted to take part to show the public how much their celebrations have meant to her, she was praised by filmmakers for her "wit, warmth and generosity" in going along with the "touching yet joyful" idea.
She had been unable to attend the Saturday night Party at the Palace concert but secured a starring role after agreeing to make a rare foray into film.
A Buckingham Palace spokesman said: "While the Queen may not be attending the concert in person, she was very keen that people understood how much it meant to her and that all those watching had a great time."
The two-and-a-half minute sketch was reminiscent of the James Bond surprise of 2012, when she played herself opposite Daniel Craig to "parachute" into the Olympic Games – to the shock of even her family.
This time, she spent around half a day filming at Windsor Castle, with palace aides declining to ruin the magic by explaining how she managed to converse with the fictional bear.
It was the result of months of planning, with Jubilee organisers keeping the surprise up their sleeves as the crowning moment of the Saturday night celebrations.
The sketch, which opened the BBC's Platinum Party at the Palace, reveals the Queen inviting Paddington Bear for a "warm and hilarious" cream tea, which goes wrong almost immediately.
Paddington – the creation of author Michael Bond and known to a generation of readers and film fans for his endearing clumsiness – deprives the Queen of her cup of tea and sprays cream from a chocolate eclair over a palace footman.
As the beloved bear shows Her Majesty what he hides underneath his hat – his beloved marmalade sandwiches – the Queen confides "So do I" and, prising open her handbag, tells him: "I keep mine in here."
The short film touched the hearts of viewers as the Peruvian-born bear congratulates the Queen on her remarkable reign, exclaiming: "Happy Jubilee Ma'am. And thank you for everything."
The monarch replies, simply: "That's very kind."
The sequence ends with both the Queen and Paddington using a spoon to tap out the beat of Queen's We Will Rock You on a china teacup.
Outside in the real world, the band and the Corps of Drums from the Bands of Her Majesty's Royal Marines struck up with the song on the main stage as the crowd tapped along.
The palace spokesman said: "Her Majesty is well known for her sense of humour, so it should be no surprise that she decided to take part in tonight's sketch.
"There was an interest in the filming and animation process and the opportunity to invite a famous bear to tea was just too much fun to miss."
Mark Sidaway, the executive producer of the BBC's Party at the Palace, described the experience of coordinating the "touching yet joyful idea" as "slightly nerve-wracking".
Rosie Alison, from Heyday Films, said: "Filming Her Majesty's tea party with Paddington Bear was such an emotional day for the entire crew. All of us were in awe of the Queen's wit, warmth and radiant aura as she patiently engaged with a polite, clumsy but very well-intentioned bear.
"Of course, she shone, and put Paddington – and all of us – at ease. Capturing this lovely encounter was an absolute joy and unique privilege for the whole team."
A spokesman for the StudioCanalfilm studio said it was a "great honour and genuine privilege" to "have been able to create this special moment".
"Filming with Her Majesty and Paddington Bear at the Palace is a memory we will all cherish. Her Majesty's warmth and generosity was a joy to behold. And who better to thank Her Majesty than Paddington, over a pot of tea, a marmalade sandwich, and with a touch of chaos. Aunt Lucy would be proud."