There is a battle playing out inside your body right now. It started billions of years ago and it is still being fought in every one of us every minute of every day. This is the story of a viral infection - the battle for the cell.
This film reveals the exquisite machinery of the human cell system from within the inner world of the cell itself - from the frenetic membrane surface that acts as a security system for everything passing in and out of the cell, the dynamic highways that transport cargo across the cell and the remarkable turbines that power the whole cellular world to the amazing nucleus housing DNA and the construction of thousands of different proteins all with unique tasks. The virus intends to commandeer this system to one selfish end: to make more viruses. And they will stop at nothing to achieve their goal. Exploring the very latest ideas about the evolution of life on earth and the bio-chemical processes at the heart of every one of us, and revealing a world smaller than it is possible to comprehend, in a story large enough to fill the biggest imaginations.

This is the dramatic global story of the first year of COVID-19, tracing the devastation caused by the spread of the virus across four continents. The way in which this coronavirus became COVID-19, transmission from animals to humans, is going on all the time. Habitat loss and live animal trading around the world that foster this is continuing. And therefore, we've got to expect that this will happen again.

Over a person's lifetime they are likely to be prescribed more than 14,000 pills. Antibiotics, cholesterol lowering tablets, anti-depressants, painkillers, even tablets to extend youth and improve performance in bed. These drugs perform minor miracles day after day, but how much is really known about them? Drug discovery often owes as much to serendipity as to science, and that means much is learnt about how medicines work, or even what they do, when they're taken. By investigating some of the most popular pills people pop, Horizon asks, how much can they be trusted to do what they are supposed to?

COVID-19 is far from the first pandemic to wreak havoc in the world. A long line of infectious diseases have devastated and in some cases destroyed entire societies. Almost all of them started in animals and made the jump to humans. The Black Death spread across Europe and Asia in the 14th century leaving millions dead in its wake. Between the 15th and 18th centuries, European colonists brought smallpox to the Americas, the Pacific region and to Australia. In Europe, the 17th century saw a series of major epidemics. And at the end of the First World War, more people died of the Spanish flu than on the battlefield.
This documentary examines the causes of these epidemics - whether it be lack of hygiene, interaction with animals, overcrowding, or the growth of cities - and how people travelling helped to spread disease and promote pandemics. It also sheds a light on the impact these infectious diseases have had on politics and societal change. Over the centuries, scientists managed to develop treatments and medicines to help control or even eradicate infectious diseases. Virologists are facing that task again with the coronavirus, as the world frantically searches for ways to overcome a pandemic which threatens our modern way of life.

Adam Rutherford meets a new creature created by American scientists, the spider-goat. It is part goat, part spider, and its milk can be used to create artificial spider's web. It is part of a new field of research, synthetic biology, with a radical aim: to break down nature into spare parts so that we can rebuild it however we please. This technology is already being used to make bio-diesel to power cars. Other researchers are looking at how we might, one day, control human emotions by sending 'biological machines' into our brains.

The film explores the revolutionary gene-editing tech now giving humankind the freedom to redraw the blueprint of biological life itself. We investigate not only the tremendous potential the technology holds, whether in the fight to eliminate diseases or in transforming agriculture to adapt to unprecedented climate extremes, but also probe the inherent risks involved and the potential for widespread abuse, dangers that could take our future down a very dark, dystopian path.