It was announced this afternoon that Brian decided to leave the house, and now it's been revealed that he climbed over the walls following an argument with Helen Wood.
The housemates played a game of 'Who's most likely to…', but it was when choosing which housemate was most likely to put themselves first, that it all kicked off.
Helen and Marc O'Neill chose Nikki Grahame, with Helen saying she can "be a bit useless and selfish" in tasks, but Brian leapt to her defence.
The argument went on to who was 'in it for the money' and Brian told Helen and Marc how he felt about them.
"When I'm in your company, around the pair of you, my energy gets so subtracted," he said. "I cannot be myself around you. You tag team people. You work in cahoots."
Brian said Helen has "no principles, morals or self- respect", leading Helen to brand Brian a "psycho."
Helen then continued to shout insults at Brian.
Arguing with both Marc and Helen, Brian went into the Diary Room, saying: "I feel like I'm being ganged up on. I don't want to cry. I've tried to keep away from there. I shouldn't have come back here. This is really hard. I feel like I'm living in hell. I'm defeated. I'm getting a barrage of abuse."
Alone in the garden in the sky room and looking over the top to the outside world, Brian climbed over the top of the wall to make his exit, with Nick Henderson too late to try to stop him.
As the other housemates ran up, Helen shouted: "It's attention!"
Show bosses have confirmed: "Helen has received a formal warning from Big Brother and Marc is about to be spoken to also."
See Brian's exit on tonight's show at 10pm on Channel 5.
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