Famed astrophysicist Neil deGrasse Tyson takes a tour of the Solar System and the known universe establishing the components of Earth's "address" within the Virgo Supercluster. He then shares the story of the person who championed an expansive understanding of Earth's place in the universe by presenting Renaissance Italian Giordano Bruno's vision of the universe as a limitless expanse of space and time. He then makes an exploration into the Cosmic Calendar, which dates back to the dawn of the Big Bang (similar to the presentation from episode 1 of the original series). The episode ends with deGrasse Tyson narrating how he met his mentor Carl Sagan, who hosted the first Cosmos series.

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.

The episode begins with Tyson describing how pattern recognition manifested in early civilization as using astronomy and astrology to predict the passing of the seasons, including how the passage of a comet was often taken as an omen. Tyson continues to explain that the origin of comets only became known in the 20th century due to the work of Jan Oort and his hypothesis of the Oort cloud. Tyson then continues to relate the collaboration between Edmond Halley and Isaac Newton in the last part of the 17th century in Cambridge. The collaboration would result in the publication of Philosophiæ Naturalis Principia Mathematica, the first major work to describe the laws of physics in mathematical terms, despite objections and claims of plagiarism from Robert Hooke and financial difficulties of the Royal Society of London. Tyson explains how this work challenged the prevailing notion that God had planned out the heavens, but would end up influencing many factors of modern life, including space flight. Tyson further describes Halley's contributions including determining Earth's distance to the sun, the motion of stars and predicting the orbit of then-unnamed Halley's Comet using Newton's laws. Tyson contrasts these scientific approaches to understanding the galaxy compared to what earlier civilizations had done, and considers this advancement as mankind's first steps into exploring the universe. The episode ends with an animation of the Milky Way and Andromeda galaxies' merging based on the principles of Newton's laws.

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.

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.