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The Best Episodes of Horizon

Every episode of Horizon ranked from best to worst. Let's dive into the Best Episodes of Horizon!

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Horizon tells amazing science stories, unravels mysteries and reveals worlds you've never seen before.

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#1 Fan Favorite
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10.0/10(1 votes)
#1 - The Mysterious Mr. Tesla
S19:E2212/20/1982
Documentary about the little known Yugoslav-American scientist Nikola Tesla, whose experiments with electricity and wireless foreshadowed the discoveries of Edison and Marconi. Some of his most spectacular experiments are recreated by the programme's presenter Robert Syme.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
10.0/10(1 votes)
#2 - Global Weirding
S49:E113/27/2012
Something weird seems to be happening to our weather - it appears to be getting more extreme. In the past few years we have shivered through two record-breaking cold winters and parts of the country have experienced intense droughts and torrential floods. It is a pattern that appears to be playing out across the globe. Hurricane chasers are recording bigger storms and in Texas, record-breaking rain has been followed by record-breaking drought. Horizon follows the scientists who are trying to understand what's been happening to our weather and investigates if these extremes are a taste of whats to come.
Director:David Stewart
Writer:Unknown
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Director:David Stewart
Writer:Unknown
10.0/10(1 votes)
#3 - Defeating Cancer
S49:E134/10/2012
Over the past year, Horizon has been behind the scenes at one of Britain's leading cancer hospitals, the Royal Marsden in London. The film follows Rosemary, Phil and Ray as they undergo remarkable new treatments - from a billion pound genetically targeted drug designed to fight a type of skin cancer, to advanced robotic surgery. We witness the breakthroughs in surgery and in scientific research that are offering new hope and helping to defeat a disease that more than one in three of us will develop at some stage of our lives.
Directors:Naomi Law, Diana Ellis-Hill
Writer:Unknown
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Directors:Naomi Law, Diana Ellis-Hill
Writer:Unknown
10.0/10(1 votes)
#4 - Eat, Fast and Live Longer
S50:E38/6/2012
Michael Mosley has set himself a truly ambitious goal: he wants to live longer, stay younger and lose weight in the bargain. And he wants to make as few changes to his life as possible along the way. He discovers the powerful new science behind the ancient idea of fasting, and he thinks he's found a way of doing it that still allows him to enjoy his food. Michael tests out the science of fasting on himself - with life-changing results.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
10.0/10(1 votes)
#5 - How Big Is the Universe?
S50:E48/27/2012
Cosmologists talk about their project to create a map of everything in existence, and also reveal that their research has some highly unexpected results, creating a picture stranger than anything they had ever imagined.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
10.0/10(1 votes)
#6 - Goodbye Cassini - Hello Saturn
S54:E149/18/2017
A billion miles from home, running low on fuel, and almost out of time. After 13 years traversing the Saturn system, the spacecraft Cassini is plunging to a fiery death, becoming part of the very planet it has been exploring. As it embarks on its final assignment - a one-way trip into the heart of Saturn - Horizon celebrates the incredible achievements and discoveries of a mission that has changed the way we see the solar system. Strange new worlds with gigantic ice geysers, hidden underground oceans that could harbour life and a brand new moon coalescing in Saturn's magnificent rings. As the world says goodbye to the great explorer Cassini, Horizon will be there for with a ringside seat for its final moments.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown

The 20 WORST Episodes of Horizon

9.0/10(1 votes)
#7 - Einstein's Unfinished Symphony
S42:E21/20/2005
The unpredictable results of the Theory of Relativity. Horizon brings you the second part of a two-part series on Albert Einsten. In the summer of 1939 Albert Einstein was on holiday in a small resort town on the tip of Long Island. His peaceful summer, however, was about to be shattered by a visit from an old friend and colleague from his years in Berlin. The visitor was the physicist Leo Szilard. He had come to tell Einstein that he feared the Nazis could soon be in possession of a terrible new weapon and that something had to be done.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
9.0/10(1 votes)
#8 - Einstein's Equation of Life and Death
S42:E31/27/2005
The story of Einstein's most famous equation E=mc² – its role in the creation of the atom bomb and our understanding of the beginnings of the Universe. Horizon brings you the second part of a two-part series on Albert Einsten. In the summer of 1939 Albert Einstein was on holiday in a small resort town on the tip of Long Island. His peaceful summer, however, was about to be shattered by a visit from an old friend and colleague from his years in Berlin. The visitor was the physicist Leo Szilard. He had come to tell Einstein that he feared the Nazis could soon be in possession of a terrible new weapon and that something had to be done.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
9.0/10(1 votes)
#9 - Little Cat Diaries
S50:E126/14/2013
50 cats were fitted with GPS collars to track their every movement, and cat-cams to record their unique view of the world. In this groundbreaking experiment, a few cats stood out. They include the intruder cat, an unneutered tomcat, who comes into the village and seems to have no owner; the hunter, who prefers food that he can catch and kill to anything his owners might buy him; and the deserter cat who has abandoned his home in favour of a new set of owners. This film reveals that the relationship between cats and their owners isn't quite what we imagine.
Director:Helen Sage
Writer:Unknown
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Director:Helen Sage
Writer:Unknown
9.0/10(1 votes)
#10 - Swallowed by a Black Hole
S50:E146/26/2013
This summer, 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.
Director:Dan Clifton
Writer:Dan Clifton
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Director:Dan Clifton
Writer:Dan Clifton
9.0/10(1 votes)
#11 - Defeating the Hackers
S51:E28/19/2013
Exploring the murky and fast-paced world of the hackers out to steal money and identities and wreak havoc with people's online lives, and the scientists who are joining forces to help defeat them. Horizon meets the two men who uncovered the world's first cyber weapon, the pioneers of what is called ultra paranoid computing, and the computer expert who worked out how to hack into cash machines.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
9.0/10(1 votes)
#12 - Man on Mars - Mission to the Red Planet
S51:E62/10/2014
Horizon goes behind the scenes at Nasa to discover how it is preparing for its most ambitious and daring mission: to land men - and possibly women - on the surface of Mars. It's over 40 years since Neil Armstrong made the first human footprint on the moon. But getting to the red planet would involve a journey of at least three years. Horizon meets the scientists and engineers who are designing new rockets, new space suits and finding ways to help astronauts survive the perils of this long voyage. And it turns out that having the 'right stuff' for a mission to mars might not be quite what you expect.
Director:Alex Hearle
Writer:Unknown
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Director:Alex Hearle
Writer:Unknown
9.0/10(1 votes)
#13 - Allergies: Modern Life and Me
S52:E38/27/2014
Changes to the bacteria that live inside all of us are responsible for increasing the number of people with allergies, suggests new research. The show investigates this claim by conducting a unique experiment with two allergic families in order to find out just what it is in the modern world that is to blame. With a raft of mini cameras, GPS units and the very latest gene sequencing technology, the show discovers how the western lifestyle is impacting their bacteria. Why are these changes making people allergic? And what can be done to put a stop to the allergy epidemic?
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
9.0/10(1 votes)
#14 - Dancing in the Dark - The End of Physics?
S52:E93/17/2015
Scientists genuinely don't know what most of our universe is made of. The atoms we're made from only make up four per cent. The rest is dark matter and dark energy (for 'dark', read 'don't know'). The Large Hadron Collider at CERN has been upgraded. When it's switched on in March 2015, its collisions will have twice the energy they did before. The hope is that scientists will discover the identity of dark matter in the debris.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
9.0/10(1 votes)
#15 - Inside CERN
S53:E138/10/2016
With exclusive behind-the-scenes access, Horizon follows the highs and lows of an extraordinary story in particle physics. In June 2015, teams at CERN started running the large hadron collider at the highest energy ever. Rumours quickly emerged that they were on the brink of a huge discovery. A mysterious bump in some data suggested a first glimpse of a brand new particle that could change our understanding of how the universe works. A new particle could hint at extra dimensions and help us understand the very beginning of the universe - but first the team has to find it. Horizon follows the scientists as they hunt for the elusive signals that would prove if there is a new particle or if it is just noise from their machine.
Director:Serena Davies
Writer:Unknown
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Director:Serena Davies
Writer:Unknown
9.0/10(1 votes)
#16 - My Amazing Twin
S53:E148/25/2016
The acerbically witty and severely facially disfigured broadcaster Adam Pearson presents a personal film about genetics. He and his twin brother Neil are genetically identical and both share the same genetic disease, Neurofibromatosis 1 (Nf1) - yet they are completely different. Adam's face is covered with growths, whereas Neil has none. Neil has short term memory loss, whereas Adam is razor sharp. How can the same genetic disease affect identical twins so differently? Adam is on the cusp of a successful film and television career, but the disease has left tumours on his face that are growing out of control and he could lose his sight. For years, everyone thought Adam's brother Neil had escaped symptoms, but today his life is governed by epilepsy and a mysterious memory loss that suddenly came on during his teens. Determined to save their future, Adam tries to find out why the disease affects the twins so differently and see if there is anything he can do to stop it from tearing their lives apart.
Director:James Newton
Writer:Unknown
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Director:James Newton
Writer:Unknown
9.0/10(2 votes)
#17 - Space Volcanoes
S54:E65/23/2017
Horizon follows an international team of volcanologists in Iceland as they draw fascinating parallels with the volcanoes on Earth and those elsewhere in the solar system. Through the team's research, we discover that the largest volcano of the solar system - Olympus Mons on Mars - has been formed in a similar way to those of Iceland, how a small moon of Jupiter - Io - has the most violent eruptions anywhere, and find out that a moon of Saturn called Enceladus erupts icy geysers from a hidden ocean. Computer graphics combined with original NASA material reveal the spectacular sights of these amazing volcanoes. Along the way, we learn how volcanoes are not just a destructive force, but have been essential to the formation of atmospheres and even life. And through these volcanoes of the solar system, scientists have discovered far more about our own planet, Earth- hat it was like when Earth first formed, and even what will happen to our planet in the future.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
9.0/10(1 votes)
#18 - Being Transgender
S54:E159/26/2017
How does a person know their gender? Do they see themselves as male or female, or somewhere in between? More and more people around the world do not identify with the gender they were assigned to at birth. Increasingly, people are expressing their gender identity outside of the 'norms', and the lines of gender are becoming more blurred than ever. This film explores what it actually means to be transgender, and what happens when a person transitions psychologically, physically and biologically. We follow a number of transgender people going through their own transition. From a socially transitioning transwoman to two young transmen embarking on hormones, to a transwoman going through gender confirmation surgery - we get a snapshot into what transitioning and being transgender is really like from those living it. We also hear from experts in the field of gender and find out how modern medicine is helping people to transition their gender. And we explore where gender identity actually comes from.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
9.0/10(1 votes)
#19 - The Battle to Beat Malaria
S60:E17/22/2024
In medical science, there’s been no longer harder fight than against malaria. This is the inside story of a historic new vaccine - from the Oxford lab behind the Covid jab. Part of the Horizon strand
Director:Catherine Gale
Writer:Unknown
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Director:Catherine Gale
Writer:Unknown
8.7/10(93 votes)
#20 - Do You Know What Time It Is?
S45:E1512/2/2008
Particle physicist Professor Brian Cox asks, 'What time is it?' It's a simple question and it sounds like it has a simple answer. But do we really know what it is that we're asking? Brian visits the ancient Mayan pyramids in Mexico where the Maya built temples to time. He finds out that a day is never 24 hours and meets Earth's very own Director of Time. He journeys to the beginning of time, and goes beyond within the realms of string theory, and explores the very limit of time. He discovers that we not only travel through time at the speed of light, but the experience we feel as the passing of time could be an illusion.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
8.5/10(2 votes)
#21 - The Secret Life of the Dog
S47:E71/6/2010
We have an extraordinary relationship with dogs - closer than with any other animal on the planet. But what makes the bond between us so special? Research into dogs is gaining momentum, and scientists are investigating them like never before. From the latest fossil evidence, to the sequencing of the canine genome, to cognitive experiments, dogs are fast turning into the new chimps as a window into understanding ourselves. Where does this relationship come from? In Siberia, a unique breeding experiment reveals the astonishing secret of how dogs evolved from wolves. Swedish scientists demonstrate how the human/dog bond is controlled by a powerful hormone also responsible for bonding mothers to their babies. Why are dogs so good at reading our emotions? Horizon meets Betsy, the world's most intelligent dog, and compares her incredible abilities to those of children. Man's best friend has recently gone one step further - helping us identify genes responsible for causing human diseases.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
8.5/10(2 votes)
#22 - What Makes us Human?
S50:E157/3/2013
Professor Alice Roberts is making a new human being - she is pregnant with her second child. But before he is born, she wants to find out what makes a human, human? What is that separates us from our closest living relatives - the chimpanzees? We share 99% of our DNA with chimpanzees and yet from the moment of birth, our lives are completely different. So are we just another animal, or is there something special about being human? Before her new baby emerges into the world, Professor Roberts sets out to explore what it is about our bodies, our genes and ultimately our brains that set us apart from our furry cousins - what is it that truly makes us human?
Director:Toby MacDonald
Writer:Unknown
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Director:Toby MacDonald
Writer:Unknown
8.5/10(2 votes)
#23 - Diagnosis on Demand? The Computer Will See You Now
S55:E1211/1/2018
Could a machine replace your doctor? Dr Hannah Fry explores the incredible ways AI is revolutionising healthcare - and what this means for all of us. This film chronicles the inside story of the AI health revolution, as one company, Babylon Health, prepare for a man vs machine showdown. Can Babylon succeed in their quest to prove their AI can outperform human doctors at safe triage and accurate diagnosis? Artificial intelligence is starting to transform healthcare beyond recognition - and tech companies large and small see almost limitless commercial opportunity. The ultimate vision is for accessible, affordable, better healthcare for almost everyone with a phone. In Britain this is already radically changing how some of us see our GPs. And in a world with a chronic shortage of doctors, but where even the very poor own mobile phones, it could be truly revolutionary. To witness this revolution from the inside, this film has privileged, behind-the-scenes access to ambitious British tech start-up Babylon Health, whose CEO Dr Ali Parsa declares with complete conviction 'we're going to do with healthcare what Google did with information.' Babylon launched its GP at Hand app in London in late 2017 and has already persuaded 30,000 Londoners to quit their old GPs to register instead for this NHS 'digital first' service, where patients discuss symptoms with an AI chatbot and see a doctor in minutes 24/7 via their phone. But GP at Hand's arrival has proved controversial - with many traditional GPs worried about the disruptive consequences for them and their patients, and others seeking to thwart its expansion nationwide. As this film reveals, there is a fundamental culture clash at play - between the 'move fast and break things' world of tech, and the cautious, diligent, often slow-moving world of medical science. So how will both camps respond when Babylon's AI attempts to pass the diagnostic sections of the Royal College of GPs exam? Amazingly, the NHS is today the largest purchaser of fax machines in the world - and the British government are eagerly embracing AI as the remedy for our public health system's antiquated inefficiencies. British health secretary Matt Hancock is an unabashed evangelist for tech - boasting Babylon's GP at Hand as his GP. Yet some scientists are increasingly alarmed, questioning the current hype and asking where is the proof that AI health apps, now in widespread use, are effective and safe. How should they be evaluated and regulated? And what needs to happen before we all trust our health to AI? As well as following a tumultuous year inside Babylon, both in the UK and Rwanda, the film also explores how another British AI Health start-up, Kheiron Medical, has successfully used deep learning to train its AI to detect breast cancer and now outperforms human radiologists at spotting the tell-tale signs of cancer in mammograms.
Director:Unknown
Writer:Unknown
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Director:Unknown
Writer:Unknown
8.3/10(3 votes)
#24 - Chris Packham: 7.7 Billion People And Counting
S57:E21/23/2020
Naturalist Chris Packham investigates the impact a growing human population is having on the planet, asking whether the earth can sustain predictions of ten billion people by 2050.
Director:Charlie Russell
Writer:Unknown
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Director:Charlie Russell
Writer:Unknown
8.2/10(9 votes)
#25 - The Truth about Fat
S49:E123/20/2012
Surgeon Gabriel Weston discovers the surprising truth about why so many people are piling on the pounds, and how to fight the fat epidemic. She discovers the hidden battles of hormones that control people's appetites, and sees the latest surgery that fundamentally changes what a patient wants to eat by altering how their brains work. Gabriel is shocked to find out that when it comes to being overweight, it is not always your fault you are fat.
Director:Tim Usborne
Writer:Unknown
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Director:Tim Usborne
Writer:Unknown

Best Episodes Summary

"The Mysterious Mr. Tesla" is the best rated episode of "Horizon". It scored 10/10 based on 1 votes. Directed by Unknown and written by Unknown, it aired on 12/20/1982. This episode scored 0.0 points higher than the second highest rated, "Global Weirding".