Britain's Got Talent contestant Miki Dark left judges Amanda Holden and Bruno Tonioli visibly shaking with his terrifying trick on Wednesday night.
The 'scary' illusionist pulled off another tense routine, leaving the audience and the judges panicked once more - but they also admitted they didn't think the act was long enough.
Just weeks on from his audition seeing him appear to set Simon Cowell on fire, this time it was Amanda and Bruno who were targeted in a trick involving a guillotine.
Bruno was told to kneel down with his head in a frame at the bottom of the execution device, which appeared to have a huge blade at the top.
This blade was being held up by a rope Amanda was tasked with holding tightly - that was until Miki made her jump and she let go.
Amanda was seen panicked as the other judges gasped, with Bruno suddenly nowhere to be seen after the blade fell.
A group of hooded assistants then appeared on stage around the apparatus, as the crowd waited to see what had happened to Bruno.
A terrified Bruno was then dragged out from behind the guillotine, with Amanda sighing with relief before hugging her co-star.
Both stars confessed they were shaken over the moment and Amanda "thought she'd killed Bruno", while Simon had run away not to be targeted again.
While viewers shared different thoughts on the trick, some eagle-eyed fans were convinced they knew exactly how he did it all.
Taking to Twitter, many viewers confessed they were familiar with guillotine themed tricks and that magicians had exposed how it was done before.
Not only that, but some viewers claimed to notice Bruno's neck "disappearing", or his head "ducking" as the blade fell.
One viewer tweeted: "Anyone else notice how long Bruno’s neck suddenly went when he was kneeling down?"
Another fan agreed: "The guillotine act is a bit tired plus the camera gave away Bruno’s head ducking down."
A third fan said: "Never seen the old guillotine trick before..." as a fourth wrote: "Pretty clear there is no bottom to that neck hole."
Meanwhile on Tuesday night, Viggo Venn and Olivia Lynes were the latest two acts revealed to have made it through after a public vote and a judges vote in the second semi-final.
First to be confirmed for the final was comedy and dance act Viggo, who shared his love for Hi Vis jackets - before getting everyone on their feet.
Despite not impressing everyone during the first audition, the act won the judges over this time as Alesha and Simon both confessed they loved his act.
The judges even claimed it was the best act of the night, and were thrilled when he made it through to the final based on the public vote.
Olivia then had to face fellow top three act Johns’ Boys, a choir group, as the judges were asked to choose which act to send through.
While Bruno saved Johns’ Boys, Simon, Amanda and Alesha all picked young singer Olivia which left her in tears.
Meanwhile, on Monday it was dancer Musa Motha and singer Amy Lou who won the first Britain's Got Talent semi-final of the series.
Talented dancer Musa, 27, was sent straight through to the final by viewers, so it went down to the judges' vote.
Ukelele musician and school teacher Abi Carter-Simpson and sunbed receptionist-turned-singer Amy Lou went up against one another.
As the judges struggled to decide, it went to the public vote and Amy Lou came second in the public vote.
There will be 10 acts in total in the live final on Sunday.
Britain's Got Talent's live semi-finals air all this week at 8PM on ITV1 and ITVX.
