The episode featured Frankie Bridge and Naughty Boy taking part in a revolting Bushtucker Trial, in which they had to down horrifying drinks at the castle camp's karaoke bar.
But fans were confused when a shot of Frankie speaking to cameras in the Telegraph had a bizarre blunder.
Eagle eyed viewers were quick to spot that as Frankie was talking, she was labelled as 'Louise Minchin' on screen. It read: "Louise Minchin. Broadcaster & Ex BBC Breakfast Host."
One viewer wrote on Twitter: "Ok so who thought Frankie was Louise?"
While another commented: "I’m going in this castle... look how much younger @louiseminchin looks! tell you what she definitely has a look of @FrankieBridge."
And a third added: "Louise looks a bit different."
"So evidently Louise and Frankie have spent so much time together, the producers can no longer tell them apart," added a fourth.
A fifth tweeted: "Oops #ImACeleb Frankie was an ex BBC breakfast host in another life named Louise?!"
And a sixth added: "Why did Louise Minchin's name just appear on the screen when Frankie was talking?!"
Last night's episode saw Frankie take on a stomach-churning trial alongside Naughty Boy. The pair managed to take home 10 out of 11 stars for camp after downing disgusting drinks including blended deer testicles.
At the end of the show, it was revealed that Naughty Boy - who has been chosen for a number of trials already by the public - has been picked again for the next challenge, Gruesome Gargoyles.
The vote was between both Naughty Boy and Matty Lee, with Ant and Dec revealing that both contestants would in fact be facing the trial together.
I'm A Celeb continues on Friday at 9pm on ITV.