X Factor 2011: Tulisa gets in the Halloween spirit in Catwomen costume

She likes to wow the audience with a glamorous outfit each week but Tulisa Contostavlos thought otherwise this week.

Embracing Halloween, the X Factor judge decided to don a black leather catsuit complete with pointy ears for tonight's special spooky show.

But she was left looking rather stupid as none of her fellow judges joined her in the fancy dress department as stand-in judge, Alexandra Burke, opted for a shimmering dress and Gary Barlow and Louis Walsh wore their normal suits.

Getting in the spirit: Tulisa Contostavlos was the only judge who wore fancy dress on last night's Halloween live show

However the N-Dubz star didn't seem too bothered about going it alone and looked happy to be showing off her trim figure in the skintight material.

Wearing a pair of skyscraper heels and buckled belt, the 23-year-old had pulled her dark hair back into a severe ponytail and unzipped her all-in-one to show off just the right amount of cleavage.

Known for being extremely dedicated to her acts on the show, perhaps Tulisa wanted her remaining groups, The Risk and Little Mix, to feel comfortable in their own Halloween make-up so she decided to join in too.

Pussy cat: The singer may have been dressed as a historic super villain but she certainly didn't act like one as he gave many of the hopefuls positive comments

She may have looked as fierce as Catwoman, but the singer certainly wasn't acting the part as she praised the hopefuls during the live show.

When Gary and Louis turned on Sophie Habibis, Tulisa disagreed with her fellow judges by telling the 19-year-old: 'You nailed it, you went for it and you're finding your own tone.'

But those weren't the only words of praise she had.

Supporting her acts: Tulisa is known for being dedicated to her hopefuls so perhaps she wanted to support them in dressing up for Halloween

After Johnny Robinson's rendition of Billy Holiday's, That Old Devil Called Love, Tulisa couldn't hide her enjoyment of his performance.

'You finally got to sing a ballad and you sung it well, she told him.

'Louis, you've been hiding his skills for too long. I loved it. Johnny, I thought you were very very sexy tonight.'

So although she wore the outfit of a historic super villain, Tulisa proved last night that she's no more than just a big pussy cat.