But there was drama as one of the girls who had been selected for the final 10 was kicked out for being too old.
Hazel Kaneswaren - who was eight months pregnant at the time of the auditions - from Dublin in Ireland was just 10 days too old according to the rules.
But 25-year-old Hazel, who was replaced by 20-year-old Kimberly Walsh, did have some good news after having a baby boy on Thursday.
The boys will live in one mansion and the girls in another during the show, with a boy being voted off the show one week and a girl the next until there are just five members of each band left.
Then the two bands are expected to battle it out for the Christmas number one spot.