Why Are Thin People Not Fat?

Season 46 - Episode 1

The world is affected by an obesity epidemic, but why is it that not everyone is succumbing? Medical science has been obsessed with this sub...

Cannabis: The Evil Weed?

Season 46 - Episode 2

Cannabis is the world's favourite drug, but also one of the least understood. Can cannabis cause schizophrenia? Is it addictive? Can it lead...

Why Do We Dream?

Season 46 - Episode 3

Horizon uncovers the secret world of our dreams. In a series of cutting-edge experiments and personal stories, we go in search of the scienc...

Can We Make a Star on Earth?

Season 46 - Episode 4

Professor Brian Cox takes a global journey in search of the energy source of the future. Called nuclear fusion, it is the process that fuels...

The Secret Life of Your Bodyclock

Season 46 - Episode 5

Why are you more likely to have a heart attack at eight o'clock in the morning or crash your car on the motorway at two o'clock in the after...

What's the Problem with Nudity?

Season 46 - Episode 6

What is wrong with nudity? Why are people embarrassed about their bodies? How and why did they get the way they are? Horizon takes a group ...

How to Survive a Disaster

Season 46 - Episode 7

When disaster strikes who lives and who dies is not purely a matter of luck. In every disaster, from those people face once in a lifetime, t...

Who Do You Want Your Child to Be?

Season 46 - Episode 8

David Baddiel, father of two, sets out to answer one of the greatest questions a parent can ask: how best to educate your child. Taking in ...

Why Can't We Predict Earthquakes?

Season 46 - Episode 9

Last century, earthquakes killed over one million, and it is predicted that this century might see ten times as many deaths. Yet when an ear...

Alan and Marcus Go Forth and Multiply

Season 46 - Episode 10

Ever since he was at school, actor and comedian Alan Davies has hated maths. And like many people, he is not much good at it either. But Ala...

How Violent Are You?

Season 46 - Episode 11

What makes ordinary people commit extreme acts of violence? Michael Portillo investigates the dark side of human nature, and discovers what ...

Do I Drink Too Much?

Season 46 - Episode 12

Do I Drink Too Much? Alcohol is by far the most widely used drug - and a dangerous one at that. So why are so many of us drinking over the r...

The Secret You

Season 46 - Episode 13

With the help of a hammer-wielding scientist, Jennifer Aniston and a general anaesthetic, Professor Marcus du Sautoy goes in search of answe...

Fix Me

Season 46 - Episode 14

Who's Afraid of a Big Black Hole?

Season 46 - Episode 15

Black holes are one of the most destructive forces in the universe, capable of tearing a planet apart and swallowing an entire star. Yet sci...

Why Do We Talk?

Season 46 - Episode 16

Talking is something that is unique to humans, yet it still remains a mystery. Horizon meets the scientists beginning to unlock the secrets ...

How Long is a Piece of String?

Season 46 - Episode 17

Alan Davies attempts to answer the proverbial question: how long is a piece of string? But what appears to be a simple task soon turns into ...

How Many People Can Live on Planet Earth?

Season 46 - Episode 18

Naturalist Sir David Attenborough investigates whether the world faces a population crisis and if it is the duty of individuals to change th...