Simon did not look happy

Ventriloquist Jimmy Tamley dragged Britain’s Got Talent judge Simon Cowell up on stage with David Walliams as part of his act on last night’s semi-final show.

Despite the judge’s protests, Jimmy decked Simon out as a larger-than-life ventriloquist’s dummy, sitting him on a stool and strapping a huge mouth mask over his head.

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David played along with the act, while a sullen Simon began to look more and more uncomfortable.

But when Jimmy grabbed Simon’s knee in an attempt to make him do the can-can, his composure seemingly cracked. Simon stormed off the stage, ripping his mask off as he went.

Eventually, he reluctantly reappeared and joined in with the last bit of the act.

But when he finally got back to his seat, he threw down the gauntlet to the show’s producers, saying: ‘When the credits roll later on you’re going to see the names of the producers who made this show. When you hear about them being murdered in two days time, I will admit I am the person.’

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BGT fans were divided over Simon’s stunt. One Twitter user described it as the ‘funniest thing to happen on this show this year’.

‘Simon really needs to get a sense of humour big time!’ another added. ‘Ventriloquist was hilarious!’

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‘Simon acted like a child,’ a third declared. ‘No need for the strop & no need to ruin someone’s performance.’

But others thought Jimmy had gone too far. ‘Didn’t like it, felt uncomfortable watching it,’ one viewer tweeted.

‘To be fair I don’t blame Simon for walking off,’ agreed another. ‘The leg grabbing trying to get him up was a bit much.’

‘In my eyes and mind this act was bullying towards @SimonCowell and humiliating!’ a third blasted. ‘@JimmyTamleyvent should have NEVER EVER touched him and forced him to do the dance!’

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But despite appearances, a BGT insider says Simon DID see the funny side.

‘Simon is absolutely fine,’ they told Metro.co.uk. ‘He’s been laughing about it during the ad break.’

The source said Jimmy’s attempt to grab Simon’s leg WAS the reason he walked off, but not for the reasons you might think. ‘It turns out the reason Simon left the stage was due to an old skiing injury,’ they explained.

‘Simon had to take the lead to stop any embarrassment. Simon thinks it was a great TV moment.’