The remaining crew members face their biggest challenge yet: finding a way through the Great Barrier Reef. If they get it wrong, this vast wall of coral could rip out the bottom of their tiny wooden boat. After two weeks with no sight of land, Restoration Island comes as a welcome relief, until Ant has an accident. As their adventure continues, the men deal with sharks, crocodiles and giant centipedes, but there's nothing more dangerous than Australia's searing heat.