In scenes that shocked and disgusted viewers last night (1 August), Marnie carried out a 'dare' to expose her naked chest at Saira while asking if a row they'd had earlier was because she "has better t*ts than" her.
At the time, Saira was visibly upset following a confrontation with several of her housemates - including Marnie - and the scenes led to Marnie being branded a "bully" by fans on Twitter. Some even called for her to be removed from CBB.
In tonight's show, Marnie will attempt to make peace with the Loose Woman presenter by telling her: "It wasn't supposed to offend you, it was just a joke, it was just a dare." Unimpressed, Saira curtly replies: "It's fine."
Stephen Bear, who set the 'dare', also attempts to apologise but she simply tells him, "it's a new day," before walking away.
Speaking to James Whale, who defended Saira when the incident happened, Saira tells him: "I don't know why I'm so emotional…I'm sick and tired of them saying sorry."
James replies: "There are certain things that are acceptable in behaviour and certain things that aren't."
Saira adds: "That's fine but it's not how I live my life - I'm not going to accept it. Instead of being sorry why don't you choose not to create an issue in the first place."
Meanwhile, TOWIE star Lewis Bloor was also in on the so-called 'dare' and he will be seen giving his view to Big Brother in the Diary Room.
"I think Saira is extremely threatened by Marnie, God knows why," he says. "The squad has said there will be no pranks with Saira today."
Last night, within minutes of the scenes unfolding, viewers took to Twitter to voice their disgust at what they had just witnessed. Former BB contestant Aisleyne Horgan-Wallace tweeted: "Marnie just went from hero to zero all in one show #cringe #cbb."
Comedian Paddy McGuinness told his followers: "I'm not struck on Saira but that Marnie kid has just gone to number 1 pr*ck in the house & that's some achievement with Bear in there. #CBB."
Attempting to defend her friend and former co-star, Charlotte Crosby spoke out and insisted Marnie will apologise to Saira in tonight's show.
Tweeting from her account, Marnie's rep added: "Just a note to everyone sending abusive tweets to this account answer one question...Have you never done anything stupid when drunk?"
In tonight's episode, Marnie also appears to share a kiss with Lewis in the storeroom. Lewis shares Marnie's rep...
CBB continues tonight at 9pm on Channel 5.
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