In episode two, we discover the golden age of the La Tene Celtic warrior and reveal how their world extended as far as central Turkey. But by the middle of the first century BC, the Celts were under threat from an expanding Roman Empire, and the Gallic warrior Vercingetorix would challenge Julius Caesar in an epic battle that would shape the future of Europe.

After the murder of his brother Frank, Al Capone is out for revenge against William Dever and the Chicago police. He plots to kill every undercover cop that was in Cicero on the day of Frank’s death. Before he can set his plan in motion, however, Johnny Torrio returns from Italy and reclaims his control of their criminal empire. Torrio forbids Capone from killing cops, fearing it would spark an all-out war. Despite Capone’s personal loss, Torrio returns to a booming business that’s raking in $10 million a month. However, as Torrio and Capone’s empire grows, it becomes harder to keep smaller factions under control. After a small group of Italian mobsters attacks one of Dean O’Banion’s distilleries, O’Banion blames Torrio and decides to end their business partnership. He announces his retirement to Torrio and offers Torrio an opportunity to buy him out. Torrio meets O’Banion at the Seine Brewery on May 19, 1924, with the buyout money. Chicago police raid the brewery and arrest Torrio while letting O’Banion walk free: O’Banion had set the whole thing up. With prior convictions, Torrio serves a mandatory prison sentence but is first released on bail. He vows to kill O’Banion as payback and gives Capone his blessing to kill O’Banion. Capone spends months planning the hit. Capone knows that catching O’Banion off guard is nearly impossible, so he places an order with O’Banion’s flower shop for nearly $20,000 worth of flowers, knowing that O’Banion personally oversees his biggest arrangements. On November 10, 1924, O’Banion works in his shop preparing the flower delivery. Two of Capone’s men enter the shop and fatally gun O’Banion down. Four days later, Chicago’s most powerful Irish gangster is laid to rest in one of the most lavish funerals Chicago has ever seen. More than two dozen cars are required to transport floral arrangements as a crowd of 10,000 mourns the death of the infamous gangster. Torrio and Capone attend the funeral, infuriating O’Banion’s top lieutenants, Hymie Weiss and Bugs Moran. Chaos breaks out as smaller gangs through the city begin a turf war. It’s the beginning of an era of bloodshed in Chicago known as the Beer Wars. Over 300 people are murdered at a rate of 75 to 100 murders a year.

After becoming the most powerful mob boss in the country, Al Capone now finds himself locked up in America's newest and harshest maximum security prison: Alcatraz. Prohibition has recently been repealed and one of the Outfit's most important sources of income dries up. With Capone cut off from all communication, his most trusted men, Frank Nitti, Tony Accardo and Paul Ricca, must keep his organization from collapsing. With Americans flocking to theaters by the thousands, the movie business is raking in millions of dollars a month. To take advantage of Hollywood, Nitti recruits Willy Bioff. Acardo breaks into a new racket in Chicago: slot machines. With help from Ricca, Accardo builds a network of slots in Chicago bars, earning up to $20,000 a year. By the end of 1939, the Outfit is bringing in more money than ever before... But new problems start to appear.

Julian Richards recalls how, after years of raiding, England's resistance was so weakened that, in the early 11th century, the Vikings were finally able to seize the throne. In other parts of the British Isles however, they gained and maintained power by integration.

Plants' solutions to life's challenges are as ingenious and manipulative as any animal's. Innovative time-lapse photography opens up a parallel world where plants act like fly-paper, or spring-loaded traps, to catch insects. Vines develop suckers and claws to haul themselves into the rainforest canopy. Every peculiar shape proves to have a clever purpose. The dragon's blood tree is like an upturned umbrella to capture mist and shade its roots. The seed of a Bornean tree has wings so aerodynamic they inspired the design of early gliders. The barrel-shaped desert rose is full of water. The heliconia plant even enslaves a humming bird and turns it into an addict for its nectar.

It was the bloodiest war in history, yet Hitler's brutal invasion of the Soviet Union and Stalin's subsequent fight back is surprisingly little known in the West. More than 30 million people died during Hitler and Stalin's terrible war in the East - more than in any other single war in history. With direct testimony from people who perpetrated atrocities and the victims who suffered on both sides, we bring the unspeakable to the screen and allowing victims and aggressors to tell the truth as they see it. In the first episode, we will look at Hitler's plans to invade the Soviet Union and the horror of the first months of conflict.