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.

With unprecedented access, the film goes deep inside a Zen Buddhist community who have given up all their possessions and signed up to a life of chastity for one common purpose - to transform their suffering, and practice the art of mindfulness with the world-famous teacher Thich Nhat Hanh.
Filmed over three years, in their monastery in rural France and on the road in the USA, this visceral film is a meditation on a community grappling with existential questions and the everyday routine of monastic life. As the seasons come and go, the monastics' pursuit for a deeper connection to themselves and the world around them is amplified by insights from Thich Nhat Hanh's early journals, narrated by Benedict Cumberbatch.

In 1914, Russia entered World War I in response to Austria-Hungary's declaration of war on Russia's ally Serbia. This was fought across multiple fronts while isolated from its allies. The Battle of Tannenberg, where the entire Russian Second Army was annihilated, cast an ominous shadow over the empire's future. The already-existing public distrust of the regime was deepened by the rising costs of the war and rumours of corruption. World War I takes Nicholas to the front. Back home, outrage grows over high casualties and Alexandra and Rasputin's political intrigues.

World War II is a watershed event for Latino Americans with hundreds of thousands of men and women serving in the armed forces, most fighting side by side with Anglos. In the Pacific, East L.A.'s Guy Gabaldon becomes a Marine Corp legend when he singlehandedly captures more enemy soldiers than anyone in US military history. But on the home front, discrimination is not dead: in 1943, Anglo servicemen battle hip young "Zoot suitors" in racially charged riots in southern California

Our universe is at war. The universe is a very violent and deadly place. Entire galaxies fight to the death. Only the strongest survive. If a galaxy wants to stay alive, it has to feed on other galaxies. Our own galaxy also fights for survival. These battles are how galaxies live, grow, and die. These collisions got us to where we are today, and they're going to determine the future of the universe.

Water plants create some of the most beautiful, bizarre and important habitats on earth. To hold on in torrents, plants use a kind of superglue. Some are armed with vicious weapons to fight titanic battles for space. Others form perfect spheres and escape from animal enemies by rolling. Where nutrients are washed away, plants turn into hunters of animals, laying traps and even counting to ensure their success.
In this episode we explore those watery worlds with David Attenborough, from Croatia to Brazil, from Colombia to Thailand, the brilliantly coloured flowers smother lakes, and in one magical river in Brazil, the water bubbles like champagne as plants create the atmosphere itself.