This episode focuses on the Jurassic period, a time when the first giant killers stalked the Earth and lurked in the seas; a time when the slightest advantage meant the difference between life and death. In North America the iconic allosaurus, an ambush hunter with a lethal bite, dominated. Not even the heavily-armoured stegosaurus was safe from this killer, and incredible evidence reveals a glimpse of a vicious battle between these two giants. Life in Jurassic oceans was no easier; in 2008, a fossil was dug out of a frozen island high in the Arctic. It was a colossal marine reptile, twice as big as most ocean predators, at 15 metres long and weighing about 45 tonnes. This was Predator X. Its skull alone was nearly twice the size of a tyrannosaurus rex's, and its bite force unmatched by anything in the Jurassic seas. The balance of power between predator and prey is a fine one, as prey continually evolves different ways to avoid predators. But for the most successful and enduring predators, the battle to survive has always been tipped in their favour

It's a timeless classic of children's literature and the third most-quoted book in English after the Bible and Shakespeare. But what lies behind the extraordinary appeal of Alice's Adventures in Wonderland to generations of adults and children alike? To mark the 150th anniversary of its publication, this documentary explores the life and imagination of the man who wrote it, the Reverend Charles Dodgson, better known as Lewis Carroll." Broadcaster and journalist Martha Kearney delves into the biographies of both Carroll himself and of the young girl, Alice Liddell, who inspired his most famous creation. Kearney's lifelong passion for Carroll's work began as a young girl, when she starred as Carroll's heroine Alice in her local village play. She discusses the book with a range of experts, biographers and distinguished cultural figures - from the actor Richard E Grant to children's author Philip Pullman - and explores with them the mystery of how a retiring, buttoned-up and meticulous mathematics don, who spent almost his entire life within the cloistered confines of Christ Church Oxford, was able to capture the world of childhood in such a captivating way

Sir David Attenborough reveals the findings of one of the most ambitious scientific studies of our time - an investigation into what is happening to our oceans. He looks at whether it is too late to save their remarkable biodiversity. Attenborough explores some of the ways in which we are affecting marine life - from over-fishing to the acidification of sea water. The film also uncovers the disturbing story of how shipping noise is deafening whales and dolphins, affecting their survival in the future.

Over a person's lifetime they are likely to be prescribed more than 14,000 pills. Antibiotics, cholesterol lowering tablets, anti-depressants, painkillers, even tablets to extend youth and improve performance in bed. These drugs perform minor miracles day after day, but how much is really known about them? Drug discovery often owes as much to serendipity as to science, and that means much is learnt about how medicines work, or even what they do, when they're taken. By investigating some of the most popular pills people pop, Horizon asks, how much can they be trusted to do what they are supposed to?

Are the wealthy just born in the right place at the right time? Are the poor victims of a system designed to keep them down? Or do physics and biology determine who is rich and who is poor? Throughout history, distribution of wealth is governed by hidden forces: DNA, environmental stress, patterns of human migration and even the laws of thermodynamics! Nature seems to demand winners and losers in life. But does this mean greed is king, and the rich can take what they want? Or is cooperation – between microorganisms, monkeys, and humans – more essential to survival of a species?

Life Cycles is a true adventure film. Over 5 years in the making, and using the bicycle as the vehicle, Life Cycles takes you on a journey through natures most beautiful, dramatic, and sometimes unforgiving landscapes.