The Britain’s Got Talent judges were shocked when finalist X revealed he was actually former contestant Marc Spelmann.
The magician has performed in a hood and white mask throughout the series.
But he took off his mask and revealed his true identity at the end of his final performance on Sunday, which centred around the word “Hope”.
“It was always about hope and never giving up,” he said as the crowd gasped and hosts Ant McPartlin and Declan Donnelly held their hands over the mouths in surprise.
“It has been an honour sharing X with you.
“I am X.”
Spelmann appeared on the ITV competition in 2018 but failed to make it to the final.
Simon Cowell told the magician he had pulled off something “incredible”.
“I never in a million years would have guessed,” he said, while fellow judge David Walliams chimed in: “Wow, wow, wow.”
Walliams added that the magician was a “master of his craft”.
Alesha Dixon said she was “dumbfounded” and that the twist made her feel emotional.
“Genuinely that is the most surprised I have ever been on this show,” she said.