Tyson begins the episode by explaining the nature of the speed of light and how much of what is seen of the observable universe is from light emanated from billions of years in the past. Tyson further explains how modern astronomy has used such analyzes via deep time to identify the Big Bang event and the age of the universe. Tyson proceeds to describe how the work of Isaac Newton, William Herschel, and James Clerk Maxwell contributed to understanding the nature of electromagnetic waves and gravitational force, and how this work led towards Albert Einstein's Theory of Relativity, that the speed of light is a fundamental constant of the universe and gravity can be seen as distortion of the fabric of space-time. Tyson describes the concept of dark stars as postulated by John Michell which are not visible but detectable by tracking other stars trapped within their gravity wells, an idea Herschel used to discover binary stars. Tyson then describes the nature of black holes, their enormous gravitational forces that can even capture light, and their discovery via X-ray sources such as Cygnus X-1. Tyson uses the Ship of Imagination to provide a postulate of the warping of spacetime and time dilation as one enters the event horizon of the black hole, and the possibility that these may lead to other points within our universe or others, or even time travel. Tyson ends on noting that Herschel's son, John would be inspired by his father to continue to document the known stars as well as contributions towards photography that play on the same nature of deep time used by astronomers.

Author and nuclear physicist Professor Jim Al-Khalili looks at what led to the discovery that everything is made of atoms. The programme looks at how the discovery affected the scientific world including the atomic energy theories of Albert Einstein and Werner Heisenberg and quantum mechanics

Professor Jim Al-Khalili investigates the most accurate and yet perplexing scientific theory ever - quantum physics. At the beginning of the 20th century scientists were led into the hidden workings of matter, into the sub-atomic building blocks of the world around us. They discovered phenomena unlike any encountered before - a realm where things can be in many places at once, where chance and probability call the shots and where reality appears to only truly exist when we observe it. Albert Einstein hated the idea that nature, at its most fundamental level, is governed by chance. Jim reveals how, in the 1930s, Einstein thought he'd found a fatal flaw in quantum physics because it implies that sub-atomic particles can communicate faster than light in defiance of the theory of relativity. In the 1960s the scientist John Bell showed there was a way to test if Einstein was right and quantum mechanics was actually mistaken. Jim repeats this critical experiment - with shocking results.

Brian Greene and an ensemble cast perform this theatrucak work tracing Albert Einstein's electrifying journey towards one of the most veautiful ideas ever conceived - the General Theory of Relativity. With state of the art animation and innovative projection techniques, Light Falls illuminates Einstein'sbreakthuroug moments, near misses, agonizing frustrations, and final emergence into the light, as one intrepid mind took on the universe... and won.
Best-selling author, superstar physicist, and cofounder of the World Science Festival Brian Greene (The Elegant Universe, The Fabric of the Cosmos) and award-winning actor Paul Rudd (Ant-Man) perform this dramatic story. Featuring an original score by composer Jeff Beal, Einstein’s electrifying journey toward his greatest achievement is brought vividly to life.

Dark energy - the mysterious force that is unexpectedly causing the universe's expansion to speed up. The effects of dark energy were discovered in 1998 but physicists still don't know what it is. Worse, its very existence calls into question Albert Einstein's general theory of relativity - the cornerstone of modern physics. The hunt for the identity of dark energy is on". Experiments on earth and in space generate data that might provide a clue, but there are also hopes that another Einstein might emerge - someone who can write a new theory explaining the mystery of the dark energy.

Ideas about time and space are explored in the changes that constellations undergo over time, the redshift and blue shift measured in interstellar objects, time dilation in Albert Einstein's theory of relativity, the designs of both Leonardo da Vinci and spacecraft that could travel near light speed, time travel and its hypothetical effects on human history, the origins of the Solar System, the history of life, and the immensity of space. In Cosmos Update, the idea of faster-than-light travel by wormholes (researched by Kip Thorne and shown in Sagan’s novel Contact) is discussed.