BBC viewers were left stunned after a contestant's "head exploded" during Lee Mack's new game show.
While BBC viewers expected to see Inside No 9, they ended up instead surprised by the comedian's new quiz programme.
Lee Mack's new show 3by3, sees three teams of three players compete for a cash prize.
Lee began: "Hello, I'm Lee Mack and welcome to 3by3, the brand new quiz show that provides three teams of three people three chances to win a big money reward.
"Well, I say big money, this is the BBC. In fact if the set doesn’t fall down we’ll be happy."
But things got a bit unsettling when the comic delivered his final comments to the camera.
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Those at home watching were left horrified as they watched one of the candidates get blown up in the background.
Margaret, Catherine's mother, was locked up in a soundproof room, where she waited until her "head blew open" live on camera.
Taking to Twitter to share their thoughts, one wrote: "What the actual f**k is going on?"
A second added: "I'm so confused! What is this 3 by 3 programme!"
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A third penned: "3 by 3 is really unnerving, anyone else?"
A fourth wrote: "3 by 3 what’s this meant to be – apart from weird? Turning over."
However, at the end of the episode, viewers learned it was all a prank and 3by3 was a made-up show based on a scene from Inside No 9.
Lee yelled to a producer and bolted off the set as the credits changed to the Inside No 9 credits.