Thirty years ago, scientists first realized that some unknown dark substance was affecting the way galaxies moved. Today, they think there must be five times as much dark matter as regular matter out there. But they have no idea what it is - onl that it's not made of atoms, or any other matter we are familiar with. And Dark Matter is not the only strange substance in the Universe - a newly discovered force, called Dark Energy, seems to be pushing the very fabric of the cosmos apart.

Beginning with the origins of the universe in the Big Bang, Sagan describes the formation of different types of galaxies and anomalies such as galactic collisions and quasars. The episodes moves further into ideas about the structure of the Universe, such as different dimensions (in the imaginary Flatland and four-dimensional hypercubes), an infinite vs. a finite universe, and the idea of an oscillating Universe (similar to that in Hindu cosmology). The search into other ideas such as dark matter and the multiverse is shown, using tools such as the Very Large Array in New Mexico. Cosmos Update shows new information about the odd, irregular surfaces of galaxies and the Milky Way perhaps being a barred spiral galaxy

This series takes viewers on a journey to the frontiers of science, where researchers are tackling some of the biggest questions about life and the cosmos. The universe is hiding something. In fact, it is hiding a lot. Everything we experience on Earth, the stars and galaxies we see in the cosmos—all the 'normal' matter and energy that we understand—make up only 5% of the known universe. The other 95% is made up of two mysterious components: 'dark matter' and 'dark energy.' We can’t see them, but we know they’re there. And what’s more —these two shadowy ingredients are locked in an epic battle to control the very fate of the universe.
Now, scientists are trying to shed light on the so-called 'dark sector' as the latest generation of detectors rev up, and powerful telescopes peer deeper into space than ever before to observe how it behaves. Will the discoveries help reveal how galaxies formed? In the series finale, Nova Wonders journeys to the stars and back to investigate what we know —and don’t know. Find out how scientists are discovering new secrets about the history of the universe, and why they’re predicting a shocking future.

Recently, the Event Horizon Telescope project captured the first image ever of a black hole. Now, new discoveries might finally reveal how supermassive black holes are made, and using the latest technology, experts are on the verge of understanding how these monsters grow and how they affect life on our planet.
Supermassive black holes: Gargantuan monsters that lurk at the center of galaxies. Right now you are travelling at half a million miles an hour around a giant black hole four million times the mass of the sun. But there's a mystery about these colossal beasts. We have no idea where they came from. How did they get so big so quickly?

It is one of the most baffling questions that scientists can ask: how big is the Universe that we live in? Follow the cosmologists who are creating the most ambitious map in history - a map of everything in existence. And it is stranger than anyone had imagined - a Universe without end that stretches far beyond what the eye can ever see. And, if the latest research proves true, our Universe may just be the start of something even bigger. Much bigger.

How and when will the Universe end? Gravity and dark matter are poised to annihilate the Universe in a big crunch. Expansion and dark energy may tear it apart. Or, a phase transition could kill us tomorrow in a cosmic death bubble.