When Homo sapiens, which means 'wise ones,' discovered and controlled fire hundreds of thousands of years ago, everything changed. Fire allowed us to cook food and heat dwellings, and it served as a focal point for storytelling and sharing cultural identity among community members. We don't yet have established parameters for what it means to be 'distinctly human,' It would seem the only thing that separates us from other animals, Neil deGrasse Tyson ponders, is our neurotic need to feel 'special'. Against the backdrop of the Halls of Extinction, Tyson insists that there must be a clear distinction between ourselves and animals that justifies our eating them, wearing them and even bringing an end to their species.
From the birth of the devil in ancient Persia to a searing story of saintliness among macaque monkeys, this episode is an exploration of human potential for change. It concludes with the story of how one of history's greatest monsters was transformed into one of its shining lights.

At 11 o'clock on New Year's Eve of the Cosmic Calendar, Homo erectus stood up for the first time, freeing its hands and earning the species its name. They began to move around, to explore, daring to risk everything to get to unknown places. Our Neanderthal relatives lived much as we did and did many of the things we consider to be 'human.' More restless than their cousins the Neanderthals and Denisovans, our Homo sapiens ancestors crossed seas and unforgiving landscapes, changing the land, ocean and atmosphere, leading to mass extinction. The scientific community gave our age a new name, 'Anthropocene.'
Since the first civilizations we've wondered if there's something about human nature that contains the seeds of our destruction. Syukuro Manabe was born in rural Japan and took an intense interest in Earth's average global temperature. In the 1960's, he would assemble the evidence he needed to predict the increase of Earth's temperature due to greenhouse gases until it becomes an uninhabitable and toxic environment, leading to our extinction. 'This doesn't have to be,' says Neil deGrasse Tyson, 'it's not too late. There's another hallway, another future we can still have; we'll find a way.'

The final episode begins with a description of the extreme cold conditions that characterized the beginning of the Holocene period, and how species like the bison and the wolf adapted to survive in these hostile environments. We will witness the majesty of the woolly mammoth and the fierce cave lion, with a vivid reconstruction of their struggles for survival. We'll see the impact of climate change during this period, from the expansion of the deserts to the transformation of the tropical rainforests of Africa into grasslands, deeply affecting primates and other animals. It highlights how these changes forced primates to adapt to life on the ground, facing new challenges and predators.
A crucial turn occurred with the emergence of humans as dominant predators and their influence on the extinction of large mammals. The documentary describes humanity's transition from hunter-gatherers to farmers, a change that radically altered the landscape and biodiversity of the planet. Finally, it poses a reflection on the current challenges of climate change and the sixth mass extinction, inviting viewers to consider humanity's crucial role in shaping the future of the Earth.