The years 1825-1918 were bloody and traumatic, a period when four tsars tried - and failed - to deal with the growing pressure for constitutional reform and revolution. In 1861, millions of enslaved serfs were freed by the Tsar-Liberator, Alexander II. But Alexander paid the ultimate penalty for opening the Pandora's box of reform when he was later blown up by terrorists on the streets of St Petersburg. Elsewhere, there was repression, denial, war and - in the case of the last tsar, Nicholas II - a fatalistic belief in the power of God, with Nicholas's faith in the notorious holy man Rasputin being a major part in his undoing. Lucy Worsley also details the chilling murder of Nicholas and his family in 1918, and asks whether all of this horror have been avoided.

Lucy Worsley continues her journey through Russia in the footsteps of the Romanovs, the most powerful royal dynasty in modern European history. In this episode she examines the extraordinary reign of Catherine the Great, and the traumatic conflict with napoleonic France that provides the setting for the novel War and Peace. At the magnificent palace of Peterhof near St Petersburg, Lucy charts the meteoric rise of Catherine the Great, who seized the Russian throne from her husband Peter III in 1762 and became the most powerful woman in the world. Catherine was a woman of huge passions - for art, for her adopted country (she was German by birth) and for her many lovers.
Catherine expanded her empire through military victories overseas, while at home she encouraged education and introduced smallpox inoculation to Russia. But Catherine struggled to introduce deeper reforms, and the institution of serfdom remained largely unchanged. Lucy explains how this injustice fuelled a violent rebellion. Nevertheless, Catherine left Russia more powerful on the world stage than ever. But all she had achieved looked set to be undone when Napoleon invaded Russia in 1812. Lucy relives the pivotal battle of Borodino, when the Russian army finally confronted the French forces; the traumatic destruction of Moscow; and, under Catherine's grandson Alexander, the eventual victory over the French that provided the Romanov dynasty with its most glorious hour.

Comet ISON can well be the brightest and most spectacular comet for a generation. It appeared above the eastern horizon from December 2013 as a glorious streak across the sky. ISON has been travelling towards the sun for ten thousand years and will make only one orbit through its corona before disappearing off into the outer solar system.
But as well as providing a great spectacle, ISON's tail of vaporised gas and water, hundreds of millions of kilometres long, will give insights into some of the greatest mysteries of science; it will help explain the origins of the solar system, whether earth's water was delivered on comets and even whether we are alone in the universe.

Award winning wildlife photographers Jonathan and Angela Scott have travelled the world, always returning home to Kenya. There they introduced the world to the big cats of the Maasai Mara and now they are part of its fight for survival.

Half of the population in Western society suffers from being overweight. Cardio-vascular diseases, diabetes and cancer are epidemic. Our meat consumption has quintupled over the past 50 years. 65 billion land animals are being slaughtered every year for food consumption. One third of the global grain production is fed to animals for fattening while 1.8 billion people worldwide suffer from hunger and starvation. Can there really be a solution to all these problems?
H.O.P.E. is a life-changing documentary uncovering and revealing the effects of our typical Western diet high in animal-based foods. It contrasts the limited interests of the pharmaceutical and agricultural industry with the all-encompassing interests of living beings on this planet and with the power of responsible consumer action. H.O.P.E. is an urgent call to action to all of us to commit to a change towards sustainability and safeguarding our living environment.

A decade after An Inconvenient Truth brought climate change into the heart of popular culture comes the riveting and rousing follow-up that shows just how close we are to a real energy revolution. Vice President Al Gore continues his tireless fight, traveling around the world training an army of climate champions and influencing international climate policy. Cameras follow him behind the scenes-in moments private and public, funny and poignant-as he pursues the empowering notion that while the stakes have never been higher, the perils of climate change can be overcome with human ingenuity and passion.
Renowned filmmakers Bonni Cohen and Jon Shenk have taken the baton from 2006 Academy Award-winner Davis Guggenheim. What started then as a profound slide show lecture has become a gorgeously cinematic excursion. Our extraordinary former vice president invites us along on an inspirational journey across the globe that delivers the tools to heal our planet. The question is: Will we choose to take the baton?