28 June 1914 and April 1945. The Story Behind two pistol shots: the single bullet, fired by a young Serb nationalist that triggered World War 1 and the self-administered shot that brought about the end of Adolf Hitler and World War 2.

4 April 1968 and February 1990. How two men - both intellectuals and determined opposers of racial oppression - came to symbolise the fight for equality as their lives for their cause.

This episode dramatises the minute by minute events leading up to the world's first ever atomic bombing. Based on extracts from President Truman's personal diaries which show the decision-making process reflecting America's real fear that the Japanese would never give up, Japanese eyewitness accounts of the tragedy in Hiroshima, diaries written on board Enola Gay, and the personal testimony of Colonel Paul Tibbets, the man who led the mission so secret not even his crew knew the enormity of what they were doing.

17 July 1918 and 9 November 1989. The Murder of the Russian royal family marked Russia's irrevocable move from a monarchy to a Communist state. Seventy Years later, the fall of the Berlin Wall symbolised the collapse of the ideology.

9 November 1938 and 14 May 1948. Just ten years after the Nazis openly attacked Jews and their property - a huge step on the nightmare spiral to the Holocaust, the 2000 year old dream of a Jewish homeland becomes a reality and the state of Israel is Born.

26 November 1922 and 17 September 1822. Two days that brought ancient Egypt dramatically to life. In 1822, Jean-Francois champollion cracks Egyptian hieroglyphs. One hundred years later, Howard Carter reads the name on a tomb and makes an amazing discovery.

2 December 1942 and 26 April 1986. The first controlled nuclear chain reaction heralded the atomic age, but Chernobyl's runaway chain reaction was the first warning. How did the most exciting scientific breakthroughs ever lead to the disaster that the world had dreaded?

In September 1970 Terrorists hijacked a number of jetliners, flew them to Jordan and kept numerous hostages to enforce their demands. In December 1988 Pan Am flight 103 was blown from the sky killing all aboard and a number of Lockerbie Scotland residents.

22 November 1963 and 8 August 1974. No one could have dreamed or anticipated the seismic shocks America suffered in the 20th century with the assassination of its youngest-ever leader and the disgrace and expulsion of its most successful election winner.

It is 19th October 1977 and Concorde taxis onto the runway at Toulouse Airport. Onboard, the crew are preparing for an historic day - the first supersonic test flight to New York. At JFK airport, protestors are waiting with a hostile welcome, but for the Concorde team and the French and British governments it is a moment that represents the end of an exhausting struggle.

14 October 1947 and 4 January 1967. Compelled by a sense of patriotic duty and driven by incredible bravery, 20 years separate the determined efforts of two mens aim to become the fastest men on the planet.