The Telegraph reports:
It was not so much a polite request to keep the noise down as a royal command, with some regal expletives thrown in for good measure.
A troupe of dancing drummers who had been pounding a beat through central London were left open-jawed when they were confronted by the Queen “effing and blinding” as she told them to be quiet.
Closer inspection revealed that it was not in fact Her Majesty giving them a dressing down but the next best thing, Dame Helen Mirren, who had stormed out of the nearby Gielgud Theatre, where she was playing the Queen, in full costume to demand that the drummers stop disturbing her performance.
To make matters yet more bizarre for onlookers, she was joined by David Cameron, played by Rufus Wright.