01. Philippines
Nigel comes face-to-face with the Philippine cobra, the most lethally venomous cobra on the planet. And in deep, dark caves on Palawan Island, the presenter searches for giant reticulated pythons sheltering from the heat of the day.
02. Brazil
Infra-red cameras in the dead of night reveals a forest pit-viper sense and strike a target just fractionally warmer than its surroundings. Then there's the mussurana - a snake that not only eats other snakes but is immune to their venom.
03. Mexico
In the tunnels of a leafcutter ant nest, we uncover a Central American coral snake sharing the burrow. Nigel meets a rattlesnake without a rattle, and a young Mexican cantil uses its white tail tip to attract prey close for a deadly strike.
04. Arabia
Snakes are highly-adapted to survive in the scorching deserts of Arabia, and Nigel's skills are tested to find his top ten. Will the saw-scaled viper's venom and lightning reflexes be a match for the backwards strike of the puff adder?