The story of British and German soldiers' photography during the First World War.
The crew of a Danish cargo ship is held hostage by Somali pirates.
Intrepid adventurer Michael Palin takes a journey through the Himalayas.
How artists have used gold, blue and white to stir emotions and alter history's course
Horizon tells amazing science stories and reveals worlds you've never seen before.
How the possibility of life on Mars has fuelled man's quest to visit the Red Planet.
Going in search of the secrets of what it takes to get a number one hit single.