Matt Hancock covered with bugs and sludge in I’m a Celebrity preview

A preview of I’m a Celebrity shows Matt Hancock crawling through dark tunnels, showered with bugs and wading through sludge.

ITV shared the teaser ahead of Wednesday night’s show, which showed the former UK health secretary squealing as insects and thick liquid are poured on him from above.

He is joined in the challenge by the comedian Seann Walsh, who was confirmed alongside Hancock as the two late entries to the series during Tuesday’s episode of the reality TV show. Hosts Ant McPartlin and Declan Donnelly announced they would go straight into their first trial, named beastly burrows.

In the preview video, the pair are seen helping each other to navigate a series of dark tunnels while wearing hard hats and feeling around for the stars that represent achievement in the trials.

At a junction, Hancock asks: “Which way do you want me to go?” prompting Walsh to respond: “I’m not a satnav, I don’t know!

The scene cuts to McPartlin and Donnelly laughing as the pair squabble.

Hancock’s decision to join the show was met with widespread criticism from parliamentary colleagues as he is a serving MP for West Suffolk and will be away from his constituents for the duration of the show, although the producers will allow him to communicate with them.

He had the Conservative party whip removed and the prime minister, Rishi Sunak, expressed his “disappointment”.

Speaking ahead of his debut on the show, Hancock said he was especially concerned about snakes, but less so about other challenges he will be facing.

Related: Public will treat Matt Hancock like a toy, says reigning I’m a Celebrity champion

He said: “I have never come across a snake at close quarters and so I am pretty worried about anything to do with snakes. I am not claustrophobic, or at least I haven’t been found to be, but that’s the thing about I’m a Celebrity – it is the unknown.”

He added: I’ve watched the show over the years, I love how it gets down to the essence of people but it’s really entertaining as well.”

Addressing whether he thinks his colleagues in parliament and the British public will be voting for him to do trials, he added: “I wouldn’t be surprised if I end up doing some of the trials. I am hoping I can win some stars for the camp, but most of all I am looking forward to being myself.”

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He said that after the show he planned to return to Suffolk to hold a surgery with his constituents there, defending his decision to appear on the show as being about finding “different ways to communicate with the public”.

He said: “We are wrong if we think you can only do that on the traditional political shows, where you are mainly only talking to people who take an active interest in politics. It’s important we engage with everyone – including young people – in who our politicians are, and this programme is a good way to do that.”

Appearing on Sky News on Wednesday, the shadow business secretary, Jonathan Reynolds, said Hancock’s appearance on the show “demeans politics and the job that we do”, adding: “Those people like Matt Hancock should remember it is a privilege to be a member of parliament.”

Reynolds said he would not be watching the series “heavily” but would be tuning in to see how Hancock was getting on.

Asked whether he would vote for Hancock to eat crocodile anus during the trials, he replied: “I think there will be a landslide across the country for Matt being volunteered for that kind of thing.”

During Tuesday’s episode, tensions grew between fellow contestants Boy George and Charlene White after the Culture Club singer described the journalist as “very controlling” over cooking and camp organisation.

Later during the episode, the comedian Babatunde Aleshe successfully completed the horrifying heights challenge, securing all nine stars and earning the maximum number of meals for camp. The former England footballer Jill Scott and Hollyoaks star Owen Warner also won a night sleeping in the more comfortable RV.

I’m a Celebrity … Get Me Out of Here! continues on Wednesday at 9pm on ITV and ITV Hub.