Watch: Sneak peek teases terrifying abseiling challenge and one trekker admits he's 'had enough' on The Summit 2023

The Summit 2023 is in full swing, but the journey to the top of the mountain is only getting harder.

And in a sneak peek for Sunday night's episode, it appears the hike might be too much for one trekker.

Stream every episode of The Summit for free on 9Now.

"My body was screaming, 'Don't do this. You'll die,'" Isaac is seen telling cameras in the footage, which you watch in full in the video above.

He's later seen storming away from the group, saying: "I'm leaving. I've had enough."

"This is the Sunday you just can't miss," the voiceover adds, as we catch a glimpse of some of the terrifying challenges the trekkers will have to face – including abseiling down a waterfall.

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"We're going to get hypothermia. We're going to die out here!" Brooke says in the clip, while hugging the other trekkers.

The camera then cuts to Jans, who is clambering across two ropes while a helicopter – the Mountain's Keeper – flies just metres away from him.

But instead of showing fear, Jans shouts: "What up brah!"

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It appears this won't go down well with the Mountain's Keeper, with the voiceover saying: "The most spectacular act of revenge will unleash fury..."

"Now she's on her way, determined to hunt you down," host Jai Courtney explains to the group, before shouting: "RUN!"

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We then see the trekkers scatter in the field and away from the low-swooping helicopter, before the trailer draws to a close.

Find out exactly what happens by tuning into The Summit, which continues Sunday at 7:00pm.

The Summit airs Sundays at 7:00pm and Monday and Tuesday at 7:30pm on Channel 9 and 9Now.