Experts suspect that the dinosaurs were wiped out after a city-sized asteroid smashed into the Gulf of Mexico causing a huge crater. But until now, they haven't had any proof. In a world first, evolutionary biologist Ben Garrod joins a multi-million pound drilling expedition into the exact spot the asteroid hit to get hard evidence of the link. The team overcomes huge obstacles as it attempts to drill 1,500 metres beneath sea level to pull up rock from the Chicxulub crater. Meanwhile, paleopathologist Professor Alice Roberts travels the globe meeting top scientists and gaining exclusive access to a mass fossil graveyard in New Jersey - believed to date from the same time the asteroid hit. Alice also treks by horseback across the remote plains of Patagonia, to see if the effects of the asteroid impact could have wiped out dinosaurs across the world - almost immediately.

Grasslands feed the world. Over thousands of years, we humans have learned to grow grains on the grasslands and domesticate the creatures that live there. Our success has propelled our population to almost seven billion people. But this episode reveals that, even today, life in the 'Garden of Eden' isn't always rosy. We walk with the Dorobo people of Kenya as they bravely attempt to scare off a pride of hungry lions from their freshly caught kill. We gallop across the Steppe with extraordinary Mongolian horsemen who were 'born in the saddle'. And in a perfect partnership with nature built up over generations Maasai children must literally talk to the birds! The honeyguide leads them to find sweet treats, but they'll have to repay the favour.

The tropical Indian Ocean is home to the Spice Islands. Characterised by beautiful sandy beaches, fringing coral reefs and coastal mangrove forests, this is a vibrant nursery area for marine life, such as whale sharks, crabs, seahorses and a great variety of fish. The coastal areas are where humans have the most direct impact on the ocean's resources.

When he killed Mehmed’s messengers, it was a message from Vlad Dracula that he would not pay his yearly dues anymore and it was clear that Vlad wanted a war against the Otoman Empire. Mehmed II sends Mara to coax Hungarian King Matthias Corvinus into an alliance. Vlad Dracula’s army was less than 30,000 men, but he invaded Bulgaria and started killing Mehmed’s men in 1462. He stole the Ottomans’ uniforms for his further attacks on the empire. Vlad also destroyed many ports that were under Sultan Mehmed II on the Danube.
Mehmed had to cross the Danube in order to reach the capital city of Târgoviște and defeat Vlad. The sultan faced the challenge of transporting 100,000 men across the river. Along with men, he had to transport cannons and horses too. The first unit to cross the river Danube included Mahmud Pasha, who was the most trusted man of Mehmed II. An epic battle along the Danube River looms, and Vlad has the upper hand.