When members of the public bought tickets to a rousing celebration of the world's best-loved classical music on Saturday night, they were promised indoor fireworks, thundering cannons and can-can girls in the aisles.
They were probably not expecting the stage of the Royal Albert Hall to become a political battleground, after a soprano donned the colours and flag of the European Union for her turn in the spotlight.
Anna Patalong, who spent Saturday at the London protest march to demand a second referendum, wore yellow and blue with a distinctive necklace of stars, in what appeared to be a defiant message to the electorate through the prism of classical music.
And as concert organisers, determined that the night not be hijacked by disagreements over Europe, asked her to change back into the dress she had worn for the previous performances, her husband took to social media to complain about her mistreatment.
The concert, called Classical Spectacular and advertised as the “UK’s most popular classical show”, has been running for 30 years at the Royal Albert Hall, loved by its fans for celebratory, flag-waving atmosphere not unlike the Last Night of the Proms.
Its programme includes highlights from Handel, Bizet, Strauss, Vaughan Williams and Verdi, with a grand finale featuring Jerusalem, Rule Britannia!, Nessun Dorma, Land of Hope and Glory and the 1812 Overture.
Performers including the Royal Philharmonic Orchestra are joined by dancers, lighting and indoor fireworks lending to the atmosphere of fun.
On Saturday night, Ms Patalong chose to wear a striking yellow dress, complete with blue sash and yellow stars, in an outfit choice she announced on Instagram as “rocking some EU colours for tonight’s concert”.
She was afterwards asked to revert to the red dress she had worn on previous nights for the Sunday show, after organisers raised fears that the evening would be misunderstood as being an appropriate space for such a political statement.
In a series of tweets beginning on Sunday, her husband, baritone Benedict Nelson, criticised the decision to ask her to change.
"Yesterday a man was ejected from the ROH for wearing a pro EU T-shirt. Today my wife was asked to change her dress from yellow and blue at the RAH as the colours were too provocative," he tweeted.
"Two artistic venues people. Anyone who knows their history knows what that sounds like."
Quoting George Orwell’s notion that “the opinion that art should have nothing to do with politics is itself a political attitude”, he added: "If you can't enjoy a three hour concert because a performer wears some visible gold stars for 3 minutes of it, you need to have a word with yourself."
A few yellow stars. How provocative. It’s quite right that people’s sensibilities were protected from such an overt and provocatively dangerous statement. https://t.co/ZVbyrdBrBr— Benedict Nelson (@ennobledinsect) March 25, 2019
Ms Patalong, a British singer who has Polish and Irish heritage, had attended Saturday's People's Vote march in London and tweeted a picture of herself with MPs Anna Soubry and Chuka Umunna.
She also accepted praise for what she termed “my tiny bit of civil disobedience” after a video showing her momentarily reconfiguring Rule Britannia to the tune of Ode to Joy at the Royal Albert Hall was shared by her husband.
Anthony Findlay, CEO of the show’s producers Raymond Gubbay, said the soprano had not been asked to change mid-show, but encouraged to go back to her original outfit for the following evening's performance.
So proud of my wonderful wonderful wife who, faced with a sea of Union Jack wavers at the Albert Hall, reconfigured Rule Britannia to the tune of Ode to Joy. She’s my hero. #PeopleVoteMarch#Brexitpic.twitter.com/7FBCboQGy2— Benedict Nelson (@ennobledinsect) March 23, 2019
"It's been going to 30 years and played to I think nearly two million people,” he said of Classical Spectacular.
"It's a celebration of classical music and has long-standing traditions in it, that's what the customers come to enjoy.
"We don't provide an arena for anything political: we never have and never will.
“We just felt that it was subject to possible misinterpretation and it doesn't feel part of the show.”
He added he was not aware of any complaints from the audience, saying he hoped the concerts were “a chance for people to put all that [European politics] aside for a moment and come and enjoy great music.”
Sign up for your essential, twice-daily briefing from The Telegraph with our free Front Page newsletter.