Who better to show us what we used to have, what's still left and what will remain after we've finished strip-mining all the world's resources and using the holes left to tip all our rubbish and pollution into? David Attenborough has been filming wild, pristine environments all over the world for decades. Now he has gone back for another look at these once virgin paradise locations and is shocked and saddened to see what has become of many of them. He's a natural optimist so he hopes there's a chance to save some of the extraordinary species and wild places before it's too late. He talks to a number of experts who give him grim statistics and a miserable prognosis for the future if we don't get a grip on environmental and species destruction soon. Over-harvesting, introduction of alien species, destruction of habitats, islandisation and pollution are all taking their toll. David wonders how we're going to go on when the human population reaches 11 billion, given the difficulty of getting people to act responsibly towards the natural world with the current (at the time the programmes were made) 6 billion.

It all sounds a bit depressing but, the programmes are full of the most fantastic images of beautiful animals and wilderness areas - and David is pretty up-beat and positive and makes the whole issue of conservation very much more interesting than most people are able to do.