Moscow, 31 December 1991: the Red Flag of the Kremlin is pulled down and replaced by the three-coloured banner of Russia, marking the end of the Soviet Union and of its ideologies. Illustrated with testimonies of top protagonists and Mikhail Gorbachev himself, the documentary recounts, day by day, the critical last two years that led to the fall of the largest and one of the most totalitarian empires of the 20th century.

Last in series about the Nazi concentration camp looks at the fate of the remaining prisoners and their guards. Uncovers how many survivors faced appalling treatment in their home countries and how many guards escaped justice.

Visit the ghostly villages surrounding Chernobyl (abandoned by humans after the 1986 nuclear disaster), travel to remote islands off the coast of Maine to search for abandoned towns that have vanished from view in only a few decades, then head beneath the streets of New York to see how subway tunnels may become watery canals. A visual journey, LIFE AFTER PEOPLE is a thought provoking adventure that combines movie-quality visual effects with insights from experts in the fields of engineering, botany, ecology, biology, geology, climatology, and archaeology to demonstrate how the very landscape of our planet will change in our absence.

Chris Lintott and Maggie Aderin-Pocock report on the reaction to the dramatic announcement of the discovery of phosphine gas in the clouds of Venus, a gas that could be a sign of life. Venus remains an inhospitable and unlikely host. But if not Venus, where in the solar system is the best place to look for alien life? Chris and Maggie investigate the latest missions to Mars and the icy moons of Jupiter and Saturn. Away from the search for life, Pete Lawrencepreviews the best meteor showers of the year.

Four years in the making, Life will set a new benchmark in family entertainment and natural history epics. Many animals and plants go to extremes to give themselves a chance. Aerial photography reveals how bottle-nosed dolphins trap fish in a ring of mud, and time-lapse cameras show how the Venus flytrap ensnares insect victims. The strawberry frog carries a tadpole high into a tree and drops it in a water-filled bromeliad. Fledgling chinstrap penguins undertake a heroic and tragic journey through the broken ice to get out to sea. Many can barely swim and the formidable leopard seal lies in wait

Reptiles and amphibians look like hang-overs from the past. But they overcome their shortcomings through amazing innovation. The pebble toad turns into a rubber ball to roll and bounce from its enemies. Extreme slow-motion shows how a Jesus Christ lizard runs on water, and how a chameleon fires an extendible tongue at its prey with unfailing accuracy. The camera dives with a Niuean sea snake, which must breed on land but avoids predators by swimming to an air bubble at the end of an underwater tunnel. In a TV first, Komodo dragons hunt a huge water-buffalo, biting it to inject venom, then waiting for weeks until it dies. Ten dragons strip the carcass to the bone in four hours.