Armed with just the clothes they're standing up in and a few basic tools, the teams are tasked with surviving on the uninhabited island, but can these modern Brits do it?
With the groups on opposite sides of the island, neither knowing the other lot is there, will they manage to find each other? And if so, can they work together and share the island's resources in order to thrive?
Their first challenge is a life or death search for drinking water as they won't survive more than a couple of days without it. With a camp to set up as well and a tropical storm on the way, can they work together and stay alive?
The Island With Bear Grylls, C4, 9pm
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