In this updated television version, produced for the BBC, Stephen Fry and Carwardine revisit the animals originally featured to see how they're getting on almost 20 years later.

The programme followed four of the last remaining northern white rhinos as they were transferred from Dvůr Králové Zoo in the Czech Republic to Ol Pejeta Conservancy, a protected reserve in Kenya, in a last-ditch attempt to save the subspecies from extinction.

At Tefé, west of Manaus, they plan to join Miriam Rosenthal and her Mamirauá team on a trip to release an injured one-year-old manatee back into the wild.

The pair then turn their attention to primates, visiting a chimpanzee rehabilitation centre and tracking mountain gorillas in Uganda's Bwindi Impenetrable Forest.

At Queen Elizabeth National Park, close to the border with the DRC, Carwardine is pleased to find that elephant numbers have increased from a handful of animals to over one thousand, showing that anti-poaching patrols are working.

At this point, Carwardine, who has been receiving news from contacts though the trip, decides that it is too risky to cross the border, as the eastern DRC is gripped by the Kivu conflict, and the journey to Garamba National Park, where the rhinos were last sighted in 2006 would involve travelling through the fighting.

After a fast and bumpy ride, they find and dart three rhinos, and transport them 100 miles to begin a new population in a fenced conservancy.

Conservationists are battling to preserve the remaining fragmented islands of forest by planting green corridors and engaging local communities.

The quest for a wild aye-aye goes on, and their perseverance is rewarded with a sighting of two animals in the same tree in Mananara Nord National Park.

At Snake Island they encounter a venomous yellow-lipped sea krait, causing Fry to rue his decision to wear open-toed sandals.

The presenters help to collect eggs from a female green turtle that has come ashore to lay, and then release new hatchlings back into the sea.

Heading further south, the pair dive and snorkel on Indonesia's coral reefs, viewing adult turtles and seahorses.

The world's largest lizard is not to be underestimated: they meet rangers and villagers who have been attacked by dragons, and hear of a child who was killed.

With protection, tolerance from locals and the ability of female dragons to procreate through parthenogenesis, Fry is confident that the species can survive.

Conservationist Don Merton takes Fry and Carwardine to the Chatham Islands, where the endemic black robin was saved from extinction by eradicating introduced predators.

At Invercargill, they enter quarantine before flying to Codfish Island / Whenua Hou where researchers are predicting a record kākāpō breeding season (they are later proved correct, with 34 eggs hatching).

They ride mules through the peninsula's desert interior to view rock art painted by the Cochimí, a Pre-Columbian civilisation.