In episode two, we discover the golden age of the La Tene Celtic warrior and reveal how their world extended as far as central Turkey. But by the middle of the first century BC, the Celts were under threat from an expanding Roman Empire, and the Gallic warrior Vercingetorix would challenge Julius Caesar in an epic battle that would shape the future of Europe.

Professor Mary Beard looks beyond the stories of emperors, armies, guts and gore to meet the everyday people at the heart of Ancient Rome's vast empire. In this programme, Mary asks not what the Romans did for us, but what the empire did for Rome. She rides the Via Appia, climbs up to the top seats of the Colosseum, takes a boat to Rome's port Ostia and takes us into the bowels of Monte Testaccio. She also meets some extraordinary Romans: Eurysaces, an eccentric baker, who made a fortune out of the grain trade and built his tomb in the shape of a giant bread oven; Baricha, Zabda and Achiba, three prisoners of war who became Roman citizens; and Pupius Amicus, the purple dye seller making imperial dye from shellfish imported from Tunisia. This is Rome from the bottom up.

Birds owe their global success to feathers - something no other animal has. They allow birds to do extraordinary things. For the first time, a slow-motion camera captures the unique flight of the marvellous spatuletail hummingbird as he flashes long, iridescent tail feathers in the gloomy undergrowth. Aerial photography takes us into the sky with an Ethiopian lammergeier dropping bones to smash them into edible-sized bits. Thousands of pink flamingoes promenade in one of nature's greatest spectacles. The sage grouse rubs his feathers against his chest in a comic display to make popping noises that attract females. The Vogelkop bowerbird makes up for his dull colour by building an intricate structure and decorating it with colourful beetles and snails.