Secrets of Britain

Scientists investigate the possibility that alien life-forms influenced human evolution, citing the existence of strange monuments around the world to support their theory.

Known as the setting of "Downton Abbey," Highclere Castle truly was the home of aristocrats and an army of servants, with a rich past to share.

Surviving power struggles, betrayals and plots, Hitler's inner circle of Nazi leaders seizes control of Germany and designs its disastrous future.

Andrew Carnegie: Rags to Riches, Power to Peace charts the story of a poor Scottish immigrant who sailed to America in the 1840s, and by the end of the century would be the richest man in the world.

A team of paranormal experts travel the UK looking into instances of paranormal activity in the homes of ordinary people.

On April 10, 1912, the RMS Titanic embarked on its maiden voyage, sailing from Southampton, England, to New York City. One of the largest and most luxurious passenger liners at the time, the Titanic was also equipped with watertight compartments, which led many to consider the ship unsinkable; an anonymous deckhand famously claimed that “God himself could not sink this ship.” On April 14, however, the ship struck an iceberg, and early the next day it sank. Some 1,500 people perished.

Experts examine the ruins and relics hidden under London. Among them, a Roman amphitheater, ditches for victims of the black plague, bomb shelters and more.

Are the self-sufficient couple how members of the royal family should be?

A tour of the Tower of London, which has served as a royal castle, prison, place of execution and torture, armory and mint during its almost 1000 years of existence.

The Tindalls are on the surface an unlikely pairing of a Wakefield-born rugby union player and the daughter of the Princess Royal born and bred in a royal palace. This programme looks at their life together, from the highs to the lows, revealing how they carved out successful careers for themselves and supported each other along the way.

Sandesh Kadur uncovers the breathtaking creatures of India.