Just when you thought the X Factor auditions couldn't get weirder, Sada Vidoo appeared before the judges announcing, very matter-of-factly, that she is a "living doll." She had certainly done her best to look the part with her delicately painted doll-like visage and dressed in a billowing pink skirt that Sharon Osbourne likened to a toilet roll cover.

But Simon Cowell wasn't having any of it. "This is ridiculous. You're not a doll," he said. "I am," she protested. "What do you do for a living?" he continues. "I am a doll," she insisted.

It was easily one of the strangest introductions on the show, prompting Simon to mutter under his breath to fellow judge Nicole Scherzinger: "You do know she's barking mad."

And then she sang. Performing the Pat Benatar song Love is a Battlefield, Sada left the judges spellbound, albeit somewhat baffled by her strangely captivating performance, complete with doll-like expressions and poses, matched with spiralling vocals.

The judges were left speechless. "You are fantastically nuts and we encourage that," said Simon. "I don't know if that's one of the best or the worst things that I have seen but that's a good thing."

"I like you because your different and I like all the mad faces," added Louis Walsh.

Her performance had viewers already drawing comparisons with Lady Gaga for her quirky persona. Appearing on The Xtra Factor, Olympic athlete Tom Daley spoke for the nation when he described her as "a little bit creepy" but altogether quite fascinating.

The audience was also torn, with some describing her as scary while others hailed her eclectic style. "The living doll woman was absolutely fabulous," said one viewer. "Not gonna lie the doll on x-factor scared me," said another.

And while Sada Vidoo certainly caught everyone's attention with her first audition, it quickly emerged that she is in fact an established singer in Denmark, who already has a record deal and has scored a platinum song.

The track, titled Infernal for dance act Ten Miles, was nominated for a Danish Club Hit of the Year Award in 2007 and topped the singles charts in Turkey, Spain, Poland and Scandinavia, Mirror Online reports.

Her album A Story with No End was released in 2014, and includes tracks The Actress, Chinadoll and her cover version of Love Is a Battlefield.

Viewers were not impressed by the revelation, with one writing on Twitter: "Sada vidoo already had a record label and album out! Not cool".

However, a spokesperson for the ITV show defended her appearance, saying: "Anyone can apply for The X Factor whether they are professional or amateur, irrespective of their past experience and all contestants are auditioned on merit. Past experience cannot always be featured in the programme due to time constraints."

A source close to the show added that the singer isn't satisfied with success in her native country and wants to be a global star. "Sada Vidoo is ambitious and wants to conquer the world with her music. She sees The X Factor UK as a platform to achieve her dream of becoming an international star."

The show also featured a singer with an uncanny resemblance to Louis Tomlinson, a Russian performer who left Simon hot under the collar and who is rumoured to be a dominatrix, and a couple, who despite Simon's best efforts, refused to be parted.

Between rows over chicken, a living doll and a dominatrix, the new series of X Factor just became strangely compelling viewing. And like Sada Vidoo, completely nuts.