Loot found secreted in pagan graves in Norway provides some major clues that point to Viking perpetrators following the discovery of murder victims in Wales and a monastery razed to the ground in Scotland.

David Attenborough discovers the plants that have evolved to shed their dependency on water enabling them to survive in the driest environments. The story begins at midnight in midsummer as David steps into the Princess of Wales Conservatory to witness the extraordinary nocturnal blooming of a cactus. The queen of the night, with its giant flowers, is the centre piece of a stunning symphony of cacti blooms that burst open in the desert (and at Kew) at night. In a mesmerizing 3D slow motion sequence, we discover the extraordinary connections between cacti and their natural pollinators: bats. As the sun rises, David meets other amazing plants. Species like the century plant, the Agave franzosini, which grows steadily for over 50 years, only to then flower itself to death with one mighty telegraph pole sized bloom which literally bursts out of the roof of Kew’s green house.

Professor Robert Bartlett explores the impact of the Norman conquest of Britain and Ireland. Bartlett shows how William the Conqueror imposed a new aristocracy, savagely cut down opposition and built scores of castles and cathedrals to intimidate and control. He also commissioned the Domesday Book, the greatest national survey of England that had ever been attempted. England adapted to its new masters and both the language and culture were transformed as the Normans and the English intermarried. Bartlett shows how the political and cultural landscape of Scotland, Wales and Ireland were also forged by the Normans and argues that the Normans created the blueprint for colonialism in the modern world.