Published Tuesday, 27 May 2014
James Smith wins the public vote on Tuesday. (© Rex Features)
Simon Cowell described the 16-year-old's acoustic rendition of CeeLo Green's hit Crazy as "faultless", telling him: "You absolutely nailed it, that was completely on the money."
He added: "It was a brilliant song choice and one of the best performances of the series so far."
"You hold people's attention with just your voice and guitar," said David Walliams.
James was overcome with emotion after the result of the public vote on Tuesday and was unable to speak to hosts Ant & Dec about his victory.
The young star will be joined in the BGT final by The Addict Initiative after the judges voted to keep them in the competition over singer Jodi Bird.
While Amanda Holden fought for Jodi to stay in the completion after her "fantastically faultless" rendition of Let It Go from the film Frozen, Simon, David and Alesha Dixon opted to put The Addict Initiative in the final.
The dance group performed a dramatic routine based on the Snow White fairy tale which David described as "brilliantly original" and "really involving".
"You definitely came to play tonight," said Alesha. "That was really powerful."
Simon added: "You are the best dance group we have had on this show since (2009 winners) Diversity."
This is real exciting talent.
Simon Cowell to The Addict Initiative
While many of Tuesday's semi-finalists earned praise from the judges for their efforts, Polish act Kony Puppets became the first act of the series to receive four red buzzers during the live shows.
The puppet act featured a collection of singing divas, including Madonna, Britney Spears and Lady GaGa, but Amanda felt the performance "really fell apart" on stage, while David "couldn't see the point".
Comedian Ricky K also heard the dreaded sound of a buzzer during his routine as Simon felt his music based act was not as funny as his original audition.
"It just wasn't my cup of tea," he told him.
Alesha agreed with Simon, adding: "It just fell flat in some places."
Songwriter Ed Drewett was hoping to finally get his chance at stardom after previously penning hits for One Direction, The Wanted and Olly Murs.
But despite receiving high praise from Alesha, Amanda and David, Simon admitted he "wasn't blown away" by his performance.
"I am happy you came on Britain's Got Talent, but I felt your vocal suffered when you went to a higher range," he said.
Ed did receive more positives responses though, with David telling him: "You have definitely got the charisma to be a star."
Other acts to perform during Tuesday's semi-final included dance group Mini Moves, girlband SweetChix and stunt act The Bolddog FMX Team.
Britain's Got Talent returns to UTV on Wednesday from 7.30pm.
© UTV News