Yesterday Iain was chosen to face his second Trial, and he speculated that his role as jungle Prime Minister may be why viewers voted for him.
"I think the public are taking their frustrations with the recent British Prime Minister out on me," he joked. "I’m not the real Prime Minister guys!"
Ant and Dec explained that the challenge would take place entirely underwater, in a large pool.
"Below this water is the Temple of Gloom, made up of a series of tunnels and chambers," Dec said. "Some have air pockets, and some are flooded, so you’ll have to hold your breath."
Iain had eleven minutes to make his way through the Temple and collect the eleven stars on offer, each representing one meal for camp.
Of course, this being a Bushtucker Trial, various water creatures were also lurking in the depths.
The starting klaxon soundd after Iain dived down to the first chamber, which had an air pocket.
He tried to enter the second chamber, where he could start collecting stars - but just seconds in he panicked and returned to the air pocket, exclaiming: "I can't do it."
Ant and Dec tried to persuade the radio host to have another go, pointing out a larger air pocket ahead.
However, after a second attempt, he decided he couldn't proceed and uttered the immortal words: "I'm A Celebrity, Get Me Out Of Here!"
Iain swiftly exited the tank, and the show's safety expert Medic Bob gave him some blasts of oxygen.
Describing the drama, he said: "I’m not a strong swimmer. That should have been ok. That box was tiny, I couldn’t catch my breath.
"I just started panicking and yeah, I ballsed up. Sorry guys, sorry kids. My kids would have loved that."
Ant offered some reassurance, saying: "When you’re down somewhere and you’re struggling with breath, you know, the one thing that is vital to survive."
The early end to the task meant the celebrities would only have rice and beans for dinner.
They rallied round Iain as he returned to camp, appearing crestfallen.
Amir Khan, who himself previously quit a Bushtucker Trial, gave a pep talk: "We are a team, we’re going to come back stronger from this."
In the Bush Telegraph, Rebekah Vardy commented: "Iain came back from the Trial basically like a broken man.
"It's really horrible, I hate seeing people upset. It brings back the reality of how desperate people are to do well, but we’re not gonna win them all."
I'm A Celebrity continues tomorrow at 9.00pm on ITV.