In the last episode, Al-Khalili turns detective, hunting for clues that show how the scientific revolution that took place in the 16th and 17th centuries in Europe had its roots in the earlier world of medieval Islam. He travels across Iran, Syria and Egypt to discover the huge astronomical advances made by Islamic scholars through their obsession with accurate measurement and coherent and rigorous mathematics.He then visits Italy to see how those Islamic ideas permeated into the west and ultimately helped shape the works of the great European astronomer Copernicus, and investigates why science in the Islamic world appeared to go into decline after the 16th and 17th centuries, only for it to re-emerge in the present day. Al-Khalili ends his journey in the Royan Institute in the Iranian capital Tehran, looking at how science is now regarded in the Islamic world

Horizon discovers what your cat really gets up to when it leaves the cat flap. In a groundbreaking experiment, 50 cats from a village in Surrey are tagged with GPS collars and their every movement is recorded, day and night, as they hunt in our backyards and patrol the garden fences and hedgerows. Cats are fitted with specially developed cat-cams which reveal their unique view of our world. You may think you understand your pet, but their secret life is more surprising than we thought.

One of the Universe's most enduring mysteries is Time Travel. In this episode, we explore the possibilities. Discover why Time Travel into the future is unavoidable in the Einsteinian world of Relativity. As for the past... the laws of physics do not tell us it's impossible, but the bizarre consequences of going into the past and altering the future make for mind-bending science. Finally, we go for the future by traveling to the nearest star, 4.3 light years away... in only 45 days. Our destination may be an Earth-like planet; a planet scientists are now hunting for, and may find in the next 3 to 4 years.

(Click CC for Subtitles) Deep in the forests of Northern Italy resides the prized white Alba truffle. Desired by the wealthiest patrons in the world, it remains a pungent but rarified mystery. It cannot be cultivated or found: the only souls on Earth who know how to dig it up are a tiny circle of canines and their silver-haired human companions-Italian elders with walking sticks and devilish senses of humor-who only scour for the truffle at night so as not to leave any clues for others. Still, this small enclave of hunters induces a feverish buying market that spans the globe.
With unprecedented access to the elusive truffle hunters, filmmakers Michael Dweck and Gregory Kershaw follow this maddening cycle from the forest floor to the pristine restaurant plate. With a wily and absurdist flare, The Truffle Hunters captures a precarious ritual constantly threatened by greed and outside influences but still somehow protected by those clever, tight-lipped few who know how to unearth the magic within nature.

This is the story of Gerald Cotten and the many people who ended up with empty bank accounts after investing in his Bitcoin cryptocurrency exchange, QuadrigaCX. What does a crypto exchange do? The movie explains it concisely and it almost makes sense: A guy like Cotten takes an investment, converts it to Bitcoin and trades it in hopes of turning a profit, kind of like a stock day trader does. Cotten ’s described as a nerdy guy who felt like an outcast, but found a community of like-minded types in the cryptocurrency world.
Cotten was in India when he got sick and unexpectedly died; he was 30. At the time, QuadrigaCX was Canada’s biggest crypto exchange, holding north of $200 million. But nobody could access the keys and passwords to the company’s accounts and, against conventional wisdom, the company had no safeguards to stop such a thing from happening. Everyone who invested their money was left grasping at empty air. Internet forums foster ideas such as Cotten faked his death and took the money. The journalists and forensic accountants who lend the voice of reason, explores the oddities in the Cotten narrative, ruling out some of the crazier stuff in a quest for the truth.

Nearly half a million years ago, the most advanced human yet roams Europe. Strong and powerful, Homo heidelbergensis are fierce hunters, use sophisticated tools and live in close-knit family groups. Over 200,000 years they become split into two populations by extremes of weather and environment and evolve separately into two very different species. In the North are the Neanderthals, whose physical power and resilience is the key to surviving in ice age Northern Europe. About 140,000 years ago, Africa is in the grip of a devastating drought, and something remarkable has happened to the descendants of heidelbergensis who live there. The combination of environment and chance has bred in them a unique ability that will change the course of human history. It will be this small band of southern survivors, perhaps numbering just a few tens of thousands, who will come to dominate the world and be known as Homo sapiens.