The first episode of this year's X Factor was watched by an average of 10.5 million people on ITV1, according to initial overnight figures.

Last year's opening episode achieved overnight figures of 11.1 million, the highest in the show's history.

The music talent show's eighth series is the first without judge Simon Cowell, who is developing a US version of the show.

Cowell was replaced by Take That's Gary Barlow. Pop singer Kelly Rowland and Tulisa Contostavlos of N-Dubz have also joined the judging panel.

Former Boyzone manager, Louis Walsh, is the only X Factor judge to remain from last year's panel.

Cheryl Cole quit to become a judge on the US version before being forced out of that role, reportedly because executives were afraid that US audiences would not be able to understand her Newcastle accent.

And Dannii Minogue left, saying the show clashed with her commitments as a judge on Australia's Got Talent.

On Saturday evening, viewers saw hopefuls including Janet Devlin from Northern Ireland, who won over the judges with her version of Elton John's Your Song, 18-year-old Frankie Cocozza and Tai Chi instructor Goldie Cheung.

ITV1's audience peaked at 12 million, the broadcaster said.

Watch the advert for this year's X Factor here: