The team investigate the incredible, natural material growing out of our heads - our hair - with access to the laboratories of some of the world's leading hair care companies. Also in HD. [S]
Dallas Campbell delves into the Horizon archive to discover how our understanding of intelligence has transformed over the last century, from early caveman thinkers to computers. [S]
Horizon follows an international team of volcanologists in Iceland as they draw fascinating parallels between the volcanoes on Earth and those elsewhere in the solar system. [S]
The Hawking Paradox: Series exploring topical scientific issues examines Stephen Hawking's most controversial theory and possibly his greatest mistake - the information paradox. Also in HD. [AD,S]