In the last of the series, Julian Richards uncovers new information from the battle in 1066 between Viking warlord Harald Hardrada and King Harold of England that marked the end of the Viking age in Britain. Results from a nationwide genetic survey show where in Britain the Vikings left a measurable contribution.

In the second episode, Andrew Carnegie builds an empire around steel, but finds himself struggling to save face after the ruthless tactics of his business partner, Henry Frick, result in both the Johnstown Flood as well as the bloody 1892 strike at the Homestead Steel Works.

On the coast, two worlds collide. Coasts are the most dynamic and challenging habitats in the ocean - that brings great rewards but also great danger. The extraordinary animals that live here must find ingenious ways to cope with two very different worlds. This episode is a rollercoaster ride of heart-stopping action and epic drama, peopled with characters from the beautiful to the bizarre. We meet fish that live on dry land and puffins that must travel 60 miles or more for a single meal, and witness a life-and-death struggle in a technicolour rock pool. In a secluded cove in the Galapagos, sea lions feast on 60kg tuna. It should be impossible - tuna are usually far too fast for sea lions to catch. But here the sea lions club together to herd their prey inshore. Once trapped in the shallows, these huge fish are easy pickings. As the tide recedes in Brazil, lightfoot crabs leap from rock to rock, desperately avoiding the water - their lives depend on it. Moray eels launch themselves from rock pools, jaw gaping. Then octopuses, too. Both crawl across dry rock to set their ambush. Elsewhere, the ever-changing tides create rock pools. But these temporary worlds are a battleground. Predatory starfish turn a magical garden into the stuff of nightmares.

The second part of the series describes how Honda withdrew from Formula 1 and how Ross Brawn and Nick Fry took control to form Brawn GP. It explains the team's financial struggles, their ingenious interpretation of the rules to develop an innovative double diffuser, and the subsequent controversies and legal battles with other teams over the legality of this innovation. The rivalry between Jenson Button, the team's lead driver, and his teammate Rubens Barrichello is emphasized. The climax of the film is Button's victory in Monaco, highlighting both the driver's triumph and the team's success under extreme pressure. As the season progresses, other teams begin to catch up to Brawn GP, increasing the pressure on Button to maintain his championship lead.
The documentary concludes with Brawn GP, pressured by financial needs, signing an agreement with Ecclestone, apparently betraying FOTA (Formula One Teams Association) and creating significant internal conflict. This twist highlights the complex power dynamics and ethical challenges within the world of F1.

After more than a century of civil war, Toyotomi Hideyoshi has united Japan. His rivals have either sworn their allegiance, or they have been destroyed. Despite this fledgling peace, Hideyoshi now dreams of a bold and outlandish plan to make himself the most powerful man in Asia. He plans to expand his reign to China. Logistical challenges and fierce operation in Korea prove to be costly.

Troop withdrawals begin as the Americans train their ARVN allies to take over the war. Gery Benedetti patrols the hostile waters of the Mekong Delta. James Anderson leads a battalion into Cambodia after Nixon's controversial order. Don DeVore struggles to survive a fierce night attack, and Anne Purcell gets promising news about her husband.