During their time in the the Australian jungle, they have faced all manner of stomach-churning tasks.

And four days before the final, John Barrowman and Fleur East will do battle with a never-ending shower of creepy-crawlies in the Rotten Retrieval bushtucker trial on Wednesday's episode of I'm A Celebrity... Get Me Out of Here!

In a teaser clip, the entertainer, 51, and the X Factor finalist, 31, let out guttural roars as they are locked in a grim underground chamber, filled with worms, beetles and spiders.

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Fleur was tasked with negotiating her way through a vile stone tunnel, littered with jungle monsters to retrieve a series of keys to free John from a prison cell.

It was no picnic for John either as he was forced to lay down in the cell while insects and worms were showered down on his head.  

The star let out a high-pitched scream as he felt the full force of the bugs rain down on him, with Fleur joining in as she fought her way through a maze of cobwebs. 

An anxious Holly Willoughby  says 'There's a few more spiders in there, Fleur.'

As Fleur exclaims 'Oh my god! Oh my god!', she boldly lifts some stars off the dingy chamber wall.

Co-host Declan Donnely says: 'Well done, Fleur, that's all of your keys.'

As Fleur screams, she is showered with yet more bugs as she shrieks 'the spiders, oh god the spiders!

'John she's got all the keys now so she's coming to get you' says Holly.

 A trembling Fleur nervously goes to unlock the cell door as she is pelted with bugs while a squirming John says 'Fleur, you got this, just fight through it' before screaming again.

As John reclines in the cell covered in meal worms, a shaking Fleur attempts to put the keys in the locks, but is taken aback by more spiders.

'Oh my god, this is torture' Fleur screams, as John lets out a high-pitched scream when a shower of insects lands on his head.

Fleur squeals: 'Jon I'm trying to save you!' as the entertainer roars. 

I'm A Celebrity continues on Wednesday, December 5 on ITV1 at 9.30pm