Among the acts performing for the judges this evening will be golden buzzer act Kyle Tomlinson and dancing policeman PC Dan.
Magician Niels Harder has already promised to wow Simon Cowell with his "dangerous stunt" which will involve host Declan Donnelly.
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.
We will be following the show throughout the evening, giving you all the latest updates from the programme.
The results will be announced after all the acts have given their performances when they will face the public vote.
See below for all the live updates from tonight’s Britain's Got Talent semi-final on ITV.
8.31pm The highly-anticipated DNA take to the stage and seem to be freaked out once again.
Simon struggles as he hasn't got his glasses and is getting flustered as he has to peruse a dictionary.
8.25pm David is not sure "what story" the group were telling but says they were cool nonetheless.
However, Simon is not very pleased and tells them they've "missed an opportunity" because no one stands out and seems uncertain about them.
8.23pm Before DNA, dance troupe Empire Dance Crew show off some dance moves with a slick routine.
8.18pm Mind reading duo DNA are set to take to the stage after the break but can they impress the judges again?
Earlier today the pair suffered a rather embarrassing moment on Good Morning Britain when a card trick went wrong live on the show. Hopefully, they will have better luck this evening.
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Bonkers magician Niels Harder performed a trick on Dec but the judges were not convinced
8.14pm David Walliams praises Kyle, who he previously dismissed from the competition for not being ready.
"I wasn't sure what to expect tonight… you absolutely amaze me," says Simon as he reveals he even closed his eyes to listen to the teen's vocals. High words of praise indeed.
8.12pm Golden Buzzer act Kyle Tomlinson takes to the stage and delivers a lovely performance of Adele's When We Were Youg.
8.08pm "You were a cross between Beyonce and Christopher Biggins, if you know who he is," says Amanda. She is not that impressed and tells him that his audition was better.
In harsh contrast, Simon does not mince his words as he brands the magician's performance as a "mess".
Kyle Tomlinson won over judges on Britain's Got Talent
8.05pm Simon is not impressed by magician Niels Harder and gives him the first buzzer of the evening. Harsh.
7.58pm Head judge Simon Cowell has just branded PC Dan's first audition as "awful" and doesn't know if he can win. Unsurprisingly, his comments are met with jeers from the audience.
But it seems both Alesha Dixon and Amanda Holden disagree with him as the latter tells him flirtatiously: "Behind the uniform is a hot bobby with some dance moves."
PC Dan throws shapes on the Britain's Got Talent stage
7.54pm Dancing policeman from Surrey PC Dan takes to the stage, he has always wanted to show a “human behind the uniform” which is why he auditioned for the show in the first place.
He appears to be on fine form with an R'n'B and pop medley that he's performing his routine to. It is certainly a step up from his audition, where he was dancing on stage by himself.
7.45pm After performing, Ant explains to the judges: "A bit of a stage issue, they couldn't hear the track, so we let them start again."
Amanda Holden appears to make reference to the Manchester attacks as she tells the choir: "After all the trauma we’ve been through over the past week, you were a breath of fresh air."
The junior choir are praised by the judges despite the initial problem but could this affect their chances?
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Dance act Just Us get the golden buzzer
7.42pm Even before the first act has begun there has already been a technical gaffe as Ant and Dec are forced to take to the stage to apologise. But eventually, St Patrick’s Junior Choir Drumgreenagh's start giving a rendition of Katy Perry's Roar. It's a beautiful performance from the school choir.
7.30pm And we're off! The first live semi-final on Britain's Got Talent this year.
Simon Cowell has admitted that he is relieved that this year he and the other judges won't be making the decision, telling Ant and Dec: "Thank goodness! We get so much grief when it's us!"
Britain’s Got Talent airs tonight at 7.30pm on ITV.