The pair came to blows again yesterday as the nominated housemates had to campaign for support to avoid eviction, and smear one of their rivals.
Unsurprisingly, Dexter chose to smear Callum and vice versa.
In the presidential style debate, Callum explained his vitriol for Dexter: "The emotion that comes up when you feel you've been bullied for seven weeks, or picked on or made an example of..."
But Dexter hit back: "Oh and I haven't since the start of the show been up every week, and you're the one that says you're being bullied? When you're the one that stands up to everybody giving it all, the big I am?"
"I'm open honest and predictable," claimed Callum, "Whereas you're sneaky, deceptive and contradicting yourself constantly.
"You're showing more of your true colours. You will stay and I will go, no issue. Batman's nothing without he Joker, you're the villain of the piece, I'd watch you, but being on the receiving end is different. You're brilliant to watch."
Dexter replied; "It's not about being brilliant to watch, it's about being true to yourself and showing raw... and exposing yourself."
Watch the task on tonight's show from 9PM on Channel 5.
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