Diarmaid MacCulloch's own life story makes him a symbol of a distinctive feature about Western Christianity - scepticism, a tendency to doubt which has transformed both Western culture and Christianity. In the final programme in the series, he asks where that change came from. He challenges the simplistic notion that faith in Christianity has steadily ebbed away before the relentless advance of science, reason and progress, and shows instead how the tide of faith perversely flows back in. Despite the attacks of Newton, Voltaire, the French Revolutionaries and Darwin, Christianity has shown a remarkable resilience. The greatest damage to Christianity was actually inflicted to its moral credibility by the two great wars of the 20th century and by its entanglement with Fascism and Nazism. And yet it is during crisis that the Church has rediscovered deep and enduring truths about itself, which may even be a clue to its future.

The second episode tells the story of the trial of Hermann Goering, Hitler's charismatic and ruthless second-in-command. On trial for his life at Nuremberg, the unrepentant Reich Marshal turned the tables on the Allies. So much so that Chief Prosecutor Justice Robert Jackson began to wish the Allies had followed Churchill's suggestion and shot the leading Nazis out of hand. This documentary drama traces the behind-the-scenes story of Goering's attempt to re-ignite Nazism from the courtroom.

Episode three explores the mind of one of the most fanatical of all Nazis and the insight that gives into the psychology of dictatorship. Hess is brought to Nuremberg from the UK where he had flown 4 years earlier much to the bemusement of the British. Overy explains that they must have quickly realised he was not normal. In the intervening time Hess’s mental state has further deteriorated and when interviewed by Chief Interrogator Colonel John Amen proclaims amnesia. Chief Interpreter Richard Sonnenfeldt explains that they brought in Göring to confront Hess but that he too failed to make an impression.
Psychopathologist Prof. Edgar Jones proposes Hess’s behaviour patterns may be his way of escaping reality as he is forced to face the extent of the atrocities and choose between accepting his part of the blame or forsaking his Führer. However, as history Professor Robert Gellatel explains it is difficult to construct a case against Hess as he was imprisoned in England when the worst of the atrocities were carried out so British Prosecutor Mervyn Griffith-Jones must argue a conspiracy charge linking the pre-1939 persecutions to the post-1939 atrocities and a crimes against peace charge proving the flight to Scotland was merely a ruse.

An unassuming 80-year-old device that has the appearance of a typewriter could actually be one of the greatest secret weapons in history. Using cutting-edge digital technology, experts investigate the secrets of a revolutionary encryption machine.
How could there be a carving of a modern helicopter on an ancient Egyptian inscription? can this 800-year-old device covered in strange sayings really predict the future?

As World War II drags on into another bitter winter the Allies become desperate to end the conflict. Winston Churchill turns to his formidable bomber force to break the deadlock.
The population of an eastern German city is caught in a devastating firestorm and harnessed by the Nazis; the controversy turns the Allies on themselves.

Hitler’s rise to power was a unique moment in history. Germany suffered a humiliating defeat in WWI; now it's crippled by massive war reparations. Hitler offers a scapegoat: the Jews. The Nazis are quick to institute anti-Semitic laws and stoke distrust of the Jews. Anyone deemed 'undesirable,' from political opponents, to the handicapped, gypsies and Jews are sent to camps. There they are either worked to death, starved or executed. But just how much did the rest of the world know of what was going on?