Richard Clay looks for what it is that has made us scribble and scratch mementoes of our lives for over 30,000 years, from prehistoric cave paintings to contemporary street art. Show more

Art historian Dr Richard Clay journeys through the dramatic and destructive years of the French Revolution, telling its history through the extraordinary story of its art. Show more

Across the world scientists are releasing predators, including panthers, bears and wolves, close to where people live. Horizon meets the scientists behind this radical scheme. Show more