The pair received the highest number of votes from the public and fended off tough competition.
They will joining mind reading act DNA and singer Kyle Tomlinson in the next round of the competition.
This evening saw performances from Destiny Chukunyere, magician Matt Edwards, singer Harry Gardner, Issy Simpson, Dizzy Twilight, Leah Barniville, Grace & Ali and dancers Taptastik.
Tomorrow night a fresh batch of hopefuls will be put on the ITV stage with two of them also going through to the final.
Golden Buzzer act Matt was forced to defend himself today ahead of the live show after a trick on Good Morning Britain did not appear to go quite to plan.
Host Eamonn Holmes was asked to select a card with a superhero on it at random but unfortunately, it the broadcaster seemed to reveal it.
Matt was going to chew a lollipop he had into the shape of the caped crusader – which turned out to be Batman.
Golden Buzzer act Matt Edwards will perform this evening
Many people pointed out that Matt would have seen the card and thus already know what character he would be creating.
The entertainer defended himself after the appearance as he explained: "The trick was more about me chewing a lollipop.
"My wife called me afterwards and told me everyone was talking about being able to see Batman – but that doesn't matter because that wasn't the trick," he told Metro.
We will be covering the second live semi-final as it happens tonight.
Follow us below for the latest news and updates from the show as it happens.
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Leah Barniville blew the judges away on Britain's Got Talent
10pm Matt Edwards and Issy have made it through to the final!
Ant wipes away Issy's tears as she says she feels "very good!"
9.59pm Issy Simpson is also in the top three as fellow magician Matt Edwards joins her.
9.58pm Grace & Ali have made the top three but who will join them?
9.53pm Everyone seems to be forgetting dancing couple Grace & Ali's name – both Simon and David had to be reminded. Amanda, too, is forgetting dancing troupe Taptastik. Oh dear.
All four agree that this is a tough call and that there is more talent this evening than the night before.
9.46pm The tension is mounting as the votes come to a close. Only a few minutes now!
9.30pm We're back as the second two acts set to go through wil be announced.
Matt Edwards was a big hit with the Britain's Got Talent judges
9pm That's it now for half an hour, join us after Coronation Street when the results will be announced.
8.59pm The phone lines are now open for the public to vote for their favourite act with the top two going through.
8.50pm Taptastik show of their fancy footwork and have three of the four judges on their feet. They have brought the show to a rousing close that the audience love.
"I think you were having a better time than I was," Simon tells them somewhat harshly but says that their second dance was better than their first audition.
"This was so much fun. You made everyone wanted to dance," Alesha tells the troupe.
Amanda praises them all and ended up plugging her performance in Stepping Out on the London stage next month.
8.43pm Dancing couple Grace & Ali give a tender performance with a routine that takes them to the next level.
Their dance has elements of La La Land with its magical and romantic feel.
"That really choked me up!" exclaims Amanda as she is moved to tears and she's not the only one as Ant is seen breaking down.
Amanda Holden was left furious over Simon Cowell's botox jibe
8.34pm Leah Barniville gets a standing ovation from the panel for her operatic performance.
"Your voice is absoultely stunning, you would 100 per cent work at the Royal Variety Performance," explained Alesha.
While Simon says there should have been better staging to make her stand out because there is some tough competition this evening.
8.29pm "I would like to see at the Royal Variety," says Amanda as Simon hails Ant and Dec for their "great choice" got the Golden Buzzer.
8.25pm Golden Buzzer act and magician Matt Edwards take to the stage with an eccentric routine.
David Walliams and Alesha Dixon appear to clash over DJ Dizzy Twilight on Britain's Got Talent
8.14pm Yesterday Simon nealy ruined DNA's trick and today that responsibility fell to Alesha, who read out a number wrong
"I messed up because I was so mesmerised," she said defending herself but David makes fun of her saying that she might have had a pre-show tipple.
8.12pm Simon has just landed himself in hot water after making a jibe about Amanda: "You use magic, you use botox, the same effect." She looks ready to throw her glass of water over him for that comment.
8.10pm Schoolgirl magician is back with more incredibly wizardry that looks like it coul have been written by J.K. Rowling.
The judges are all standing and are amazed – as are the audience, judging by that reaction from the audience.
Dizzy Twilight got a mixed reception from the Britain's Got Talent judging panel
8.06pm Alesha says that she was thinking of her own grandmother during Harry's performance and her heart was "pounding".
"What you did was very brave and years back you will look back at this," Simon tells him.
8.02pm Harry Gardner is set to leave viewers in tears with another stirring performance. He has again paid tribute to his grandmother, who suddely passsed away since his audition.
7.54pm David and Alesha Dixon look like they are going to clash over their opinion of the 66-year-old act.
"I don't know how much talent the is there," Amanda Holden just harshly tells Dizzy Twilight. But Simon Cowell brands it "professional jealousy" as he defends her.
Britain's Got Talent dancers Taptastik will perform this evening
7.53pm Dizzy Twilight certainly has the crowds up on their feet, including David who is loving the DJ set.
7.50pm Next up is Dizzy Twilight, who is one of the biggest surprises of this year's Britain's Got Talent. She may be one of the most unique and inspiring acts in the history of the show.
7.40pm It's the first act all the way from Malta, singing sensation: Destiny Chukunyere. She is putting plenty of soul into her performance as she showcases her incredible voice to the judges.
Britain's Got Talent: Most memorable moments Mon, May 1, 2017
Britain's Got Talent: The best and worst moments from the ITV talent show.
ITV 1 of 51
Dance act Just Us get the golden buzzer
7.35pm Has there just been another gaffe for a second night running? Ant and Dec both look nervous as they say the first act is running late and "not quite ready".
7.30pm AND… we're off with the second semi-final live!
"I think it's very important that it's variety going forward," says judge David Walliams, explaining that he wants to see a number of different acts in the final.
Britain’s Got Talent airs tonight at 7.30pm.