After eight days in the wild, four celebrities remain and it's clear that the physical strain is taking its toll.The group are led to an estuary. For a survivor, this is a lifeline which means food, water and more importantly, a means of travel. It does, however, also have its dangers, and in South Africa that means Bull Sharks.The celebrities are split into two teams. Their task; to build a raft that will get them across the estuary safely. The tide is coming in and with it the risk of a shark attack increases. Time is running out. Working in pairs, will it be a case of two heads are better than one, or will heads butt? Staying calm under pressure is key, but can they keep it together?Once across they have to prepare their camp. With a place in the final within reach, Bear wants to see what they have learnt as individuals. The celebrities must each build their own shelter. But the rookies have no idea that Bear has one further test. In the dead of night he sends Meg and Scott into camp with a surprise they won't forget.The next day Bear meets the group at the mouth of the estuary. The celebrities are already aware of the importance of staying hydrated, however what do you do when there's no clean water available? Never asking the group to do anything he is not prepared to do himself, Bear sets them the task with a rather personal demonstration which shocks the celebrities.Will they take up his challenge or walk?With one last chance to prove to Bear that they deserve to be in the final, the remaining celebrities must navigate their way along the dangerous Southern African coast. They take on the jagged rocks and dangerous swells.Bear has been watching closely. For one more celebrity, the journey is over, and for the remaining three the race to become Bear's ultimate mission survivor is closer than ever.