Alesha Dixon admitted she knew one Britain's Got Talent act during the first batch of live auditions as the ITV series returned on Saturday.
Simon Cowell, Amanda Holden and new judge Bruno Tonioli were left stunned by the revelation with Alesha later revealing she knew the musician from her days in noughties girlband Miss-Teeq.
The admission came when community choir The Big Sing, made up of singers from ages 3 to 83, walked on stage.
Audtionee Gemma explained she helped to create choir along with her husband Howard.
"We're a community choir, we're just made up of normal people who love to sing and we sing really uplifting music to make you feel good," she said.
As Simon greeted Howard, Alesha interjected: "I actually know Howard very well."
The music moguel continued with the introductions as Gemma told Simon that her three-year-old daughter Eden is the youngest member of the choir.
"What's the big dream here?" Simon asked and the singer replied: "We want to get as many people singing as possible. We just want people to come and join us and enjoy the love of singing."
As they began their performance, Bruno asked Alesha how she knew the pianist.
"He used to play for Miss-Teeq," Alesha, who rose to fame in noughties girlband Miss-Teeq.
The Big Sing went on to perform their rendition of Brighter Days by Emeli Sandé but it wasn't long before all four judges were dealt a huge shock.
A voice appeared from the audience and then a large number of singers stood up from the crowd.
As the performance continued, more and more audience members joined in while the judges got up on their feet.
Members of the BGT audience that weren't in the choir soon joined them in a standing ovation as well as singing along.
At the end, one of the singers told Ant McPartlin and Declan Donnelly that there was a total of 350 choir members in the audience.
Praising the performance, Alesha said: "How do we sum this up? I just felt so joyful through the whole thing. Outstanding," before Amanda added: "It reminded me of the scene in Wizard of Oz where everything is in black and white and then the magic happened."
After impressing all four judges, The Big Scene were sent through to the next round.
Britain’s Got Talent launches on Saturday 15th April, 20:00 and continues on Sunday 16th April, 19:45 on ITV1 and ITVX.
