Danny Dyer branded boxing legend Chris Eubank a "t**t" after he constantly kept pulling him up on his swearing.
The former EastEnders star called him 'useless' on Scared of the Dark - but told viewers they'll be right behind him.
The Channel 4 series, which kicks off on Sunday night, will see the celebrities live, eat and sleep in the dark.
It will also feature football icon Paul Gascoigne, Scarlett Moffatt, Chris McCausland, Donna Preston, Chloe Burrows, Max George and Nicola Adams - and they have all escaped presenter Danny's grilling.
In the opening hour-long episode the eight contestants and host Danny say “f***” a total of 90 times as they try to cope with living for up to eight days in the pitch black.
Danny was speaking ahead of the programme's launch this weekend.
He was asked about the most badly behaved celeb and was in no doubt about who he had to pick.
He said: "I suppose badly behaved in the sense of being a bit of a t**t was probably Eubank, weren’t it? He’s on a journey as well, by the way.
"I think there’s a moment in this where you’re really rooting for Chris as well, by the way.
"He’s such an emotional man, and he does really open up about some stuff which is important for the show."
Danny added: "Chris as it goes on, you’ll see that he’s the f***ing man in there. He's the f***ing alpha. Eubank, who’s the f***ing boxer, the physicality.
"He’s useless in there, and that comes right to the front."
Danny also admitted that he and Chris clashed during their time working together, as Chris scolded him for his bad language.
He explained: "It was interesting, the swearing thing. He boll***ed me, and it was cut out, and I swore, and he gave it to me about swearing.
"So I thought, ‘Oh, okay. So now I’m going to encourage every other fu**er that you’re allowed to swear when you walk in, because when everybody walked in, they went ‘Oh f**inghell!’ and I see him just cringing.
“But yeah, he bo****ked me early about swearing, He doesn’t like that, does he?”
Bear Grylls’ The Island is thought to hold the record for the sweariest British show, with one episode in 2016 including 67 “f***s”, 23 “sh**s” and one “c***”.
Scared of the Dark airs Sunday at 9pm on Channel 4.