In a first-look clip ahead of Monday night's show, radio DJ Shy and Emmerdale star Miller are shown looking horrified by their first bushtucker trial - The Castle's Dreaded Diner.
Read more: Meet the I'm A Celebrity 2021 campmates
Miller was shown in last night's series opening episode panicking about the prospect of eating revolting items as he said he thought it would make him sick.
The clip from tonight's task shows a miserable-looking Miller retching over his opponent's meal - a "sneezeburger" which turns out to be a cow's nose sandwiched into a burger bun.
It doesn't go down much better with Shy, who springs out of her seat screaming and bursts into tears when she sees the nose.
Typically, hosts Ant and Dec laugh along at the celebrities' reactions to the trial, which sees them sat opposite each other at a diner table as their sick buckets are placed alongside them.
Miller and Shy are competing to win meals for their respective camps - the soap star is in the losing team with David Ginola, Naughty Boy, Arlene Phillips and Richard Madeley who are living in basic conditions after losing last night's games.
Shy is hoping to bring another slap-up dinner back to her winning team of Louise Minchin, Kadeena Cox, Matty Lee and Frankie Bridge in the main camp, but viewers will have to tune into the ITV show tonight to see who is triumphant.
Last night's series opener saw Minchin and Shy win a walk the plank challenge ahead of Miller and Naughty Boy, while Cox and Lee championed in the forest task ahead of Ginola and Phillips.
Madeley and Bridge had been voted into the first bushtucker trial by viewers and had to complete a series of levels on a tower unscrewing keys while critters were dumped on them, with Bridge named the victor.
The show has returned to Gwrych Castle in Abergele, Wales for a second year and is set to welcome another two campmates later in the series.
I’m A Celebrity…Get Me Out Of Here! airs on Monday 22 November at 9pm on ITV and ITV Hub
Watch: Who is I'm A Celeb's Snoochie Shy?