A Britain's Got Talent viewer was convinced he had rumbled how magician The Phantom performed his act on Saturday's show.
In a mystifying act, The Phantom performed an invisible magic trick on the judges. The performance started with Amanda Holden's buzzer going off - despite no one touching it.
She was then invited on stage to sit in a chair and hold a red balloon. Around 10 seconds after taking hold of the balloon it randomly popped.
Amanda was then asked to look inside a box and pick one item without looking and place it under a piece of paper. The box was then handed to Alesha Dixon.
She was asked to take the remaining item out of the box. Using 'compulsion' The Phantom asked Amanda to name what item Alesha had in her hand.
Amanda said the first thing that popped into her head was a dummy, which Alesha then revealed she was holding. Amanda was then asked to place a piece of chalk on a chalkboard.
Without any assistance, The Phantom then proceeded to write the word 'keys' on the board. Amanda then lifted the piece of paper from earlier to reveal she had picked out a set of keys from the box.
The Phantom then played a videotape of someone taking David Walliams' house keys from his dressing room earlier that day. The keys Amanda had picked were revealed to be David's.
While the judges were left starstruck by the act, one viewer on Twitter thought he had cracked the magician's tricks. Adam Richardson tweeted: "BGT weird invisible act: 1) Buzzer triggered by the lighting technician as it always is remotely.
"2) Chalkboard with a magnetic track behind it and a magnet in the chalk - they filmed the scene in Matilda the same way.
"3) ITV camera crew around the dressing room."
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