Michael Portillo looks at the science behind executions.

Psychologists subject six volunteers to a world without stimulation.

Dr Brian Cox wants to know why the Universe is built the way it is.

A trip through the highs and lows of the UK’s 20 most dangerous drugs.

Lifting the lid on the business of human choices in an exclusive guide to making better decisions.

While scientists have been searching for the secrets of long life, a few isolated communities have stumbled across the answer.

Friendly bacteria, superfoods, cholesterol busting spreads, 99% germ free, whiter than white...it's almost impossible to find a product in the supermarket today that doesn't come with impressive claims...a scientific claims, but do they actually do what they say? Are they worth the price? Are they worth a place in Prof. Regan's shopping trolly?

Use the Drake equation to calculate the number of civilisations in our galaxy.

Horizon investigates the medical revolution that has created an almost insatiable demand for body parts .

Horizon journeys into the human memory, from how it emerges in childhood, develops through to adulthood, and fades in middle age.

Horizon asks some of the biggest names in science to have a quiet word with the new American president. The United States president is quite simply the most powerful man on earth, but past presidents have often known little about science. That is a problem when the decisions they make will affect every one of us, from nuclear proliferation to climate change.

First of a two-part special. Ten volunteers have come together for an extraordinary test. Five are 'normal' and the other five have been officially diagnosed as mentally ill. Horizon asks if you can tell who is who, and considers where the line between sanity and madness lies.

Second part of the special documentary considering where the line between sanity and madness lies as ten volunteers come together for an extraordinary test.

Jimmy Doherty, pig farmer, one-time scientist and poster-boy for sustainable food production is on a mission to find out if GM crops really can feed the world.

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?

We are in the grip of an allergy epidemic. Fifty years ago one in 30 were affected, but in Britain today it is closer to one in three. Why this should be is one of modern medicine's greatest puzzles.

Danny Wallace really wants a robot. He wants it to walk like him and talk like him. It's what scientists have been promising us for generations but it's a promise so far unfulfilled. Danny circumnavigates the globe searching for robot nirvana, trying to uncover how far away his dream is.