Just Us are a dance group from The Wirral, made up of best friends Alice (17), Poppy (14), Julia (15), Annie (17) and Rebecca (16).
They met at their local dance school and they put the five piece dance group together a few years ago.
"No one's ever going to come between our friendship and that's why it's just us," the girls told cameras.
The group said they had been practising until midnight ahead of the audition in a bid to perfect their routine for the judges.
Speaking to panel before their performance, Julia revealed she has Scoliosis and will soon undergo surgery which will leave her unable to dance.
"This is my last chance and I've always wanted to do it," she said.
"You've got an amazing attitude," Simon Cowell told her.
Just Us go on to perform to Rachel Platten's Fight Song.
After the routine, a teary Alesha Dixon said: "I have so much admiration for you girls right now, I can't tell you. Seeing how you come together, when you're passionate about something I can't imagine not being able to ever do that again.
"I really couldn't and that's why we all live, for the things we love to do. It really touched me."
She then hit the golden buzzer to send the group straight into the live shows.
"It was an absolutely stunning performance, it's a beautiful story about friendship," David Walliams added.
Britain's Got Talent 2017 is back Saturday night at 8PM on ITV with More Talent straight after on ITV2 from 9:20PM.