In the concluding episode of the series, Jim encounters ever larger cosmic structures to reveal the latest breakthroughs in our understanding of the universe. For example, Jim comes face to face with our galactic home, the Milky Way, a monstrous structure sculpted by the gravitational forces of dark matter. Jim finds out from pioneering researcher Adrian Fabian about the black hole at its centre, whose strange behaviour includes emitting the lowest note that can be heard in the cosmos.
At an even greater scale, Jim encounters huge structures such as the Laniakea Supercluster, of which the Milky Way is only a tiny part. Then there’s the 'Giant Arc', a collection of galaxies that account for more than three per cent of the observable universe. Jim learns from its discoverer, British PhD student Alexia Lopez, that this gargantuan structure is forcing scientists to reassess their theory of how the universe evolves and may overturn some of the most fundamental principles in physics.

How did the universe come to be? Thanks to a series of discoveries, our most powerful space missions have unravelled 13.8 billion years of cosmic evolution and revealed the story of our universe from its birth all the way to the arrival of our nascent civilization. Our guide on this odyssey back to the dawn of time is light. Telescopes are time machines - by looking out into the distant universe, they open a window to the past. One telescope more than any other has helped us journey through the history of the universe: NASA’s Hubble Space Telescope. Remarkably, Hubble has even found one of the first galaxies ever to exist in the universe, which was born some 13.4 billion years ago. It's a discovery that hints at the beginnings of our own Milky Way. Vivid CGI brings this ancient galaxy to life, allowing us to witness for ourselves the first dawn. It was the beginning of a relationship between stars and planets that would, on a faraway world, lead to the origin of life - and ultimately to us.
Hubble’s incredible discoveries have allowed scientists to piece together much of our cosmic story, but it cannot take us back to the most important moment in history: the Big Bang. For decades, the moment the universe began was the subject of pure speculation, but by combining astronomy and cosmology, scientists have finally found a way to put their theories to the test and study the momentous events that took place during the Big Bang. They can do this because the European Space Agency’s Planck space telescope has seen the afterglow of the Big Bang itself – something we call the Cosmic Microwave Background. The unparalleled detail Planck gave us has helped confirm something remarkable: the Big Bang may not be the beginning. There was a time before the dawn – a place beyond anything we can comprehend. Professor Brian Cox transports us back to the fraction of a second before the Big Bang, when the seeds of our universe were planted.

Take an express journey to the edge of the universe as the filmmakers use computer-generated animation to build on images captures by the Hubble Telescope. The animation and story telling absolutely wonderful. Beginning on planet Earth, viewers are hurtled into the deepest reaches of space. There are no stops on this flight, and along the way the mysteries of the universe come alive as we examine the history and science of distant celestial.

Embark on an astounding journey across 100,000 light-years to witness key moments in the history of the Milky Way. Using cutting-edge science, National Geographic constructs a 3-D state-of-the-art CGI model of our galaxy. We'll peer into the heart of the Milky Way on the hunt for super-massive black holes, watch how stars are born and die, fly out and above the plane of our galaxy to understand its true shape and scour its dusty spiral arms for the possibility of life

The black hole at the centre of the Milky Way is getting ready to feast. A gas cloud three times the size of our planet has strayed within the gravitational reach of our nearest supermassive black hole. And across the globe, telescopes are being trained on the heart of our Milky Way galaxy, some 27,000 light years from Earth, in the expectation of observing this unique cosmic spectacle. For cosmic detectives across the Earth, it is a unique opportunity. For the first time in the history of science, they hope to observe in action the awesome spectacle of a feeding supermassive black hole.

Carl Sagan opens the program with a description of the cosmos and the Spaceship of the Imagination. The ship journeys through the universe's hundred billion galaxies, the Local Group, the Andromeda Galaxy, the Milky Way, the Orion Nebula, our Solar System, and finally the planet Earth. Eratosthenes' successful calculation of the circumference of Earth leads to a description of the ancient Library of Alexandria. Finally, the Ages of Science are described, before pulling back to the full span of the Cosmic Calendar.