Alesha Dixon and Amanda Holden will be seen clapping and dancing in their seats to Britain's Got Talent act The 100 Voices Of Gospel.
The international choir features singers who hail from all around the world, including America, Britain, France and Africa.
In Saturday's episode, their spirited rendition of gospel classic This Little Light Of Mine visibly moves Dixon and Holden.
Fellow judges Simon Cowell and David Walliams and hosts Ant and Dec will join in the acclaim for the singers.
Before their audition, the group's American lead singer is awed at the prospect of appearing on the Royal Variety Performance, the grand prize for the winning act.
"Our choir consists of 20 nationalities. We have lawyers, policemen, nurses - it's a family affair," she is heard to say.
"If we got the opportunity to perform before the royal family, that's the opportunity of a lifetime."
Viewers will have to wait until Saturday's episode is broadcast to find out if the singers secured any yeses from the judges.
Jack Higgins from Liverpool evokes the plot of Billy Elliot with his appearance and audition.
Like the character Jamie Bell plays in the award-winning movie, the 14-year-old has a love of ballet.
"I don't have any other hobbies, it's just dance, dance, dance for me," he says before he walks on the stage.
"When I started ballet, people were calling me names ... I was getting really upset, but dancing, it just makes me feel happy."
Jack's love of dancing has made him the target of bullies.
As his proud mother watches from the sidelines, the teenager performs a ballet routine to Say Something by A Great Big World.
The dancer's "ultimate dream" is to win the ITV talent series.
But first, he has to win over the panel.
The show may be called Britain's Got Talent (BGT), but that has not stopped the flow of performers from outside the UK.
Mexican juggler Roberto Carlos, Polish dance group Fair Play Crew, and Another Kind of Blue - a duo from Italy and the Netherlands - all opted for the UK version of the Got Talent franchise.
Fans will soon find out if their gambit paid off.
Wayne Woodward, a 20-year-old builder from Sutton, proves one cannot judge a book by its cover.
His speaking voice is apparently similar to EastEnders actor Danny Dyer.
"You sound exactly the same," the former Mis-Teeq member says in the episode.
"Nah. He sounds like me!" Woodward replies.
Viewers will see how surprised the judges are when he performs The Way You Look Tonight, originally sang by Hollywood star Fred Astaire.
Other acts hoping to win the panel's approval include retired 73-year-old magician Mel Harvey, and 60-year-old Bill Brookman, a one-man band on stilts.
:: Britain's Got Talent is broadcast on ITV at 8pm.