Each band performs two songs, before the viewers decide which band should win.
Two of the bands are guaranteed a place in the final, while the other two must sing again.
Take That perform with the contestants, before the boys are tested on their dance skills.
Following the viewer vote, the two bottom bands must sing again to impress the judges.
The remaining contestants have been put into five bands and must now perform live.
The contestants perform in groups, joined by a big name in British music.
The first audition stage reaches its conclusion.
The hopefuls continue to audition in front of the studio audience and the judging panel.
The hopefuls face judges Gary Barlow, Dannii Minogue, Martin Kemp and Amber Riley.
Gary Barlow welcomes you into the world of boybands and musical theatre.
Five new boy bands have been born. Get to know them better with this first look.