During the audition stage, Niels wowed viewers as he left fellow host Anthony McPartlin just moments from death as he volunteered to put his neck on the line in Niels's Guillotine of Death.
As the Guillotine sliced two cucumbers in half, Ant's neck was luckily left in tact, but will the same happen for his co-host Dec?
Niels teased tonight's performance to Express.co.uk, revealing: "There's a dangerous act, sexy boys on stage and I want to make Simon go wild.
"I use Dec in my act and it will be live and dangerous," the 26-year-old hinted.
Niels Harder revealed tonight's stunt will involve lots of "sexy boys"
Ant put his neck on the line during Niels' audition
There's a dangerous act, sexy boys on stage and I want to make Simon go wild
The Dutch magician also revealed that he has an unusual batch of celebrities as inspiration for his unique act.
Niels explained: "I come up with all my illusions myself, but I find inspiration from Beyoncé, Michael Jackson, Katy Perry and Lady Gaga.
"I put them all together and you get Niels Harder, one crazy magician," he joked.
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He also believes he will be loved by the Royal Family, should he manage to win the ITV talent show.
"I think the Royal Family will say, 'Niels you are so crazy, baby!’" the so-called "Weirdo of Wonder" laughed.