The three acts from each category then compete in the live shows with continuing help from their mentors.
Once chosen, the acts compete for cash prizes at the actual event.
Eight acts competed for three spots in the semi-finals.
Nine acts competed for four spots in the final.
Three acts (previously two for series 1 and 3) competed in the final for the £1 million recording contract.
Six acts will compete each week and only two will manage to pass.
In each episode, six acts competed with one of them being the winner from the previous episode.
In the fourth programme six acts will compete, the two of which get the least votes will be eliminated.
The top 36 acts will compete for the live semi-finals round for six weeks.
No scoring is used, and the judges' votes aren't revealed, but the acts that win their semifinals then compete in the championship show.
