Music's hottest star and the British monarch came face to face in Blackpool on Monday after a typically flamboyant performance from the American singer.
Perhaps in homage to the royal guests of honour – the Queen was joined by her husband Prince Philip – the 23-year-old star wore a red latex outfit with a ruffle inspired by Elizabeth I and a 20 foot train.
That bold wardrobe choice teamed with glittering red eye makeup and her platinum blonde locks, the self-confessed "massive fan" of the Queen stole the show.
Her performance was no less spectacular than her costume. To close the event, she was hoisted in to the air to play on the piano her new single, Speechless – written for her father who was proudly watching from the audience.
Lady Gaga wasn't the only star from the States performing in Blackpool. Miley Cyrus, 17, gave an energetic performance in a daring pair of hot pants.
Home-grown talent included X Factor winner Alexandra Burke, Britain's Got Talent winners Diversity and Katherine Jenkins.
Lulu, Anastasia and Chaka Khan opened the show with Take That's Relight My Fire at the event, also attended by Whoopi Goldberg and popular Canadian singer Michael Buble.
Comedian Peter Kay was the host on the night, and he welcomed the royal party to the "the entertainment capital of the world" as the charity gala got underway.
He also added that his Nan was sitting near the monarch, quipping they would be "swapping fudge by the interval".