She is one of the most memorable housemates to take part in the Big Brother experience.

Now Nikki Grahame is heading back into the house for a third time in a bid to shake up this year's show.

The season seven favourite - famous for her temper tantrums and catchphrases such as 'Who IS she?' - will be a resident of a 'secret lair' alongside last year's winner Helen Wood.

Scroll down for video

Reality legend: Nikki Grahame is heading back into the house for a third time in a bid to shake up this year's show

This Friday's evictee will join the pair in the room away from the main house, where they will spy on their fellow contestants in secrecy.

This week's nominees for eviction are Irish stripper Marc, personal trainer Sam and Mr. Showbiz Simon.

It's the latest twist in this series - airing on Channel 5 - and follows the 'four in four out' night, where four housemates were evicted and replaced with four new contestants.

It will Nikki's second return to the BB house. Following her showstopping original appearance in 2006, she returned in 2010 for Ultimate Big Brother, which pitted the best contestants from the normal and celebrity versions against each other.

Spirited: The Londoner was an instant hit with viewers due to her tantrums and catch-phrases during her first stint in 2006

Love story: Nikki fell for fellow housemate Pete Bennett, who went on to win the seventh series

Nikki - who romanced fellow housemate and 2006 winner Pete Bennett during her first stint in the house - previously hinted she was going to return to the show.

She at the time: 'I'm not going in tonight but I would quite fancy doing 'I'm A Celeb' before I go back in the house. I don't want to spoil any surprises.'

The 33-year-old star is also adamant that she 'mellowed' since her first time on the show.

She added: 'I was a real crazy character, wasn't I? But that was like ten years ago. I had a lot of nervous energy. I've mellowed.'

Facing the chop: This week's nominees, including Marc and Simon, could end up in a secret lair with Nikki if they get the boot

Up for nomination: Sam is also facing eviction after receiving nominations from housemates

Meanwhile, Helen - who is known for having reportedly slept with footballer Wayne Rooney - has revealed she wants to stir things up when she enters the lair.

She said: 'I want to go in and stir up a hornets nest. Who the f**k wants to sit and watch a bunch of people getting along?'

The former prostitute was one of the franchise's most controversial winners when she triumphed last year.

2012's CBB champion Denise Welch was so unhappy at Helen winning, she wrote: 'bbuk I've just heard. I'm appalled. I'm upset.'