As John-James, 20, performed the song from the musical Joseph and His Amazing Techicolour Dreamcoat, David Walliams, Alesha Dixon and Amanda Holden happily sang along while waving their arms in the air, along with the rest of the Belfast crowd.
Before voting 'yes', Amanda told him: "It's a classic that song and it's a crowd pleaser."
She jokingly added: "Your cloak was beautiful, I could see it."
Unfortunately Simon Cowell was not as impressed with John-James' performance as the rest of the panel, but did praise his "likeability".
"Do I hear you making records, I'm not so sure," he said.
Simon's comments were met with boos from the audience, prompting David to jump to his feet and implore his fellow panellist to "listen to the people for once".
While David, Amanda and Alesha each voted yes, Simon was not to be swayed and voted no. Luckily for John James he had the three yes votes he needed to move forward in the competition.
"Auditioning for the show was a wonderful experience," he told u.tv.
"Meeting the judges, Ant and Dec and Stephen Mulhern was an extra special treat and communicating with the other acts beforehand made me a couple of new friends.
"I'm hoping that the people like me!"
You need to have a strong backbone in musical theatre and I think you're made of titanium and I think you did brilliantly.
Amanda Holden to Jodi Bird
Also performing a number from the world of musical theatre was 16-year-old Jodi Bird from Wales.
The young hopeful sand Don't Rain On My Parade, but while the majority on the panel were enjoying her rendition, Simon was not happy with her song choice and abruptly stopped her during her audition.
He told her: "I can't listen to that. Can I hear something else a little less smiley and just a better song."
The remaining judges were soon up in arms over Simon rude interruption, with David telling her: "I think it's a shame Simon cut that short."
Determined to finish her audition, Jodi confidently told Simon there was more to the song, before he agreed to let her finish, resulting in a standing ovation from the audience.
"You really won us over and that's what we're looking for, someone with passion and someone who wants to win and I really got that from you," said David.
Alesha said: "I really like you Jodi. That song is full of personality so really well done."
"I may have acted a little bit prematurely there," said Simon. "I'm not crazy about those songs and I did cut you off too short and I apologise...
"Actually no I'm glad I did that because you proved a point. You came back with more excitement and more determination, and I kind of did it on purpose now that I'm thinking about it.
"Sometimes you've got to push people little. So I'm actually taking credit for that performance."
There are a lot of people who are great songwriters but that doesn't necessarily make them good performers but you do look and sound like a star.
David Walliams to Ed Drewett
One hopeful who was lucky enough not to face Simon was songwriter Ed Drewett, who performed during the London auditions when Simon was called to New York for the birth of his son.
Ed told the remaining panel he wrote a number of well-known chart hits, including The Wanted's All Time Low and One Direction's Best Song Ever.
The 25-year-old performed an original song called Blink and also earned a standing ovation from the audience.
"I've always thought the songwriters are the real stars because you're the ones who make the artists who they are," said Alesha.
"That is such a fantastic song! It's so catchy, I feel like I know it already."
Amanda added: "The lyrics were beautiful. I am totally gutted that Mr Simon Cowell isn't here because I think he would love you."
The final auditions of the series also included puppets dancing to Beyonce, drag act La Voix performing with The London Gay Big Band, Joe Poulton introducing the judges to 'The Prawn' and the latest craze for dogs - doggy disco.
Britain's Got Talent returns to UTV next Sunday.