This week, Steve journeys through the remote rainforests of Guyana, where he has a close call with a big black caiman, gets hands-on with the unpredictable giant bird-eating tarantula, swims alongside deadly electric eels and gets a rare sighting of the endangered giant river otter, a fearless pack hunter that can devour an entire caiman.

In episode four, Steve is in Australia, infamous as the ‘home of the deadly', with more lethal snakes than any other country, dangerous spiders, great white sharks and salt-water crocodiles.