In the opinion of many of the most important scientists in the world, our planet is currently experiencing its greatest mass extinction in 66 million years. Since the start of the fossil record, 800 million years ago, five major extinctions have preceded this one, each in turn devastating the earth. Cosmic cataclysms, major climatic changes, continental drifts and chemical alterations of the oceans appear to be responsible for the first five. Man is responsible for the sixth. Candidates to Extinction is a documentary on the causes and effects of these apocalyptic catastrophes that have wiped out some 99% of all the species that have existed on the face of the earth since the origin of life. In this way, we will analyse the repercussions of this new mass extinction which our species is causing. In the course of this documentary, we will see the worst case of pollution in the history of the World, when certain bacteria living in the primeval slime 3,000 million years ago began to produce a gas which was highly toxic for the life forms then existing: oxygen, a gas that would change the planet. We will relive the devastating moment when life, which up to then had fed on chemical elements and the sunlight, began to devour itself. We will also see the movements of the former continents, whose collisions and drifts brought death to millions of species. And we will travel back in time to witness the impact of asteroids which, at different times, changed the oceans, covered the sky with ash, blocking out the sunlight, and, among others, wiped out the largest animals that have ever inhabited the land surface: the dinosaurs. But this documentary is not just a story of cataclysms. Mass extinctions gave rise to new beginnings, new ages of experimentation in forms of life. In the course of the documentary, the current man-made extinction will lead us to consider the repercussion of past extinctions on the life of our planet, and how this reacts and recovers. In this way, we will be able to see the possibilities of a surprising future: the Earth will recreate life after the changes that we have generated but, probably, and if we are not capable of changing the process of this sixth extinction, ours will be among the species that have disappeared forever.