Hunger, sickness and extreme weather are just some of the problems the group must face when they're dropped into forested wilderness in a remote area of Bulgaria.
Swapping their smart phones for animal skins, they find their new camp is basic – equipped with primitive tools, rations and a pile of flint. They're helped out at first when they're given a freshly killed deer, but vegetarian Josie doesn't cope well with that.
They've got only hours to go before nightfall, and it looks like they're in for a cold, hungry night.
10,000 BC, Channel 5, 10pm
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