Exoplanets, strange worlds outside our solar system. We're discovering the cosmos is full of alien planets. Alien worlds that challenge our understanding of planetary systems. Hellishly hot worlds, violently colliding worlds, worlds getting eaten by their stars. There's much, much more out there than we had ever imagined.
Exoplanets are shaking up our understanding of the universe. The cosmos is a chaotic array of the odd, the weird, and the wonderful. The more we find, the less we know.

In the fifth episode Neil deGrasse Tyson explores questions that have baffled scientists for centuries. Can we know the universe? Are our brains capable of comprehending the cosmos in all of its complexity and splendor?. We don't yet know the answers because our brain remains almost as much of a mystery to that questions as the universe itself. An abandoned orphan's dream opened the way to understanding the architecture of thought.

The Vision After the Sermon, also known as Jacob Wrestling with the Angel, is a painting full of symbolism and mystery. But what does Gauguin’s famous work have to do with a 17-year-old girl called Madeleine, with Victor Hugo’s Les Miserables, and with sumo wrestlers?
Waldemar Januszczak reveals all as he investigates Gauguin’s epic religious painting about good and evil, temptation and desire.

The last episode examines the fragile interdependence that exists between forests' wide variety of residents, including bald eagles, hunting dogs and Siberian tigers.
Over half of all the world's trees, evergreen and deciduous, stand in great assemblies. For many of us, they are places of mystery and darkness. They are key to our climate, and home to countless unique species. The boreal forest contains 750 billion trees, and it stores over 40 percent of the world's carbon, making it a vital element in the fight against climate change. In the past, we have destroyed them without hesitation. Yet, forests do have an astonishing ability to recover. If we choose to give forests time and space, they could reclothe the earth with much of the rich and varied communities of animals and plants of which we have, so recently, robbed it. A future with more forests is key to the resilience of our planet.

'Stangest Things' series examines those hidden gems that have been tucked away in museums, laboratories and storage rooms around the world. Experts use the latest technology to investigate these incredible artifacts of history.
A bizarre find called Copper Scroll is one of the famous Dead Sea Scrolls, but it's unlike any of the others; this strange relic might hold clues to a long-lost treasure, and cutting-edge science may finally reveal answers to this billion-dollar mystery.

The Obsidian Mirror is a mysterious artefact crafted from volcanic rock, and it's said to be a device used to communicate with supernatural beings; experts use cutting-edge tech to discover who made this strange relic and why.
A golden disc can answer the biggest mystery of all: Are we alone in the universe? The Voynich manuscript is one enormous puzzle. What secrets are hidden in this bizarre 600 year old book that nobody can read?