Having entered the house as a special guest on Tuesday, Gillian initially chose Stephanie Davis, Tiffany Pollard, Scotty T and John Partridge to spend a night in the toxic clinic.
However, Gillian warned that she could swap housemates at any time, and she did just that as she revealed to the house on Wednesday who would be going into the clinic next - and two of them had to return!
Stephanie was told she would be going back in because she "didn't take advantage of a great opportunity presented to you and you produced a very smelly poo".
Jeremy McConnell was also picked to go into the toxic clinic, which made Steph ecstatic.
"This is also a chance for the two of you to handle yourselves differently when you're in close proximity," said Gillian. "So, please don't let me down. I don't want to feel like this is a big mistake."
Tiffany was told she would be going back in for not making the most of the opportunity. "You need more purification and this will be very good for you. And you're drinking again and that breaks my heart," Gillian told her.
Last, Gillian told Darren Day that she had chosen him because he is "emotionally holding and severely constipated". However, he didn't seem too impressed and was a little disappointed to be picked.
So, the four chosen housemates named as toxic are Stephanie, Jeremy, TIffany and Darren. They will spend one night in the toxic clinic.
CBB airs nightly on Channel 5.
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