Season 1

It was Hitler’s deadliest secret - his scientists had promised him an atomic bomb. If he got it first, Nazi domination was assured. But the Germans needed one ingredient, heavy water which was only produced in one factory, deep in the heart of occupied Norway. In 1943 a team of Norwegian raiders was sent to destroy it - their success or failure could decide the outcome of the war.

In late 1943, the Resistance asked for help - some of their top operatives were being held in Amiens prison and facing interrogation, torture and execution. They must be rescued. The plan which evolved depended on a very special aircraft - the Mosquito fighter-bomber - and the skill and courage of its pilots in flying low enough to breach the prison walls with their bombs.

As RAF Bomber Command began to strike back at Nazi Germany, it was soon suffering unsustainable losses from the Nazi air defence system. At its heart were as yet unidentified radar systems using wavelengths which urgently needed to be cracked. At last, in December 1941 a key German radar installation was located at Bruneval near the French North Sea coast, and a team of Britain's new paratroops were sent in to seize it.

The great dry dock at St Nazaire was the only one on the Atlantic coast of occupied Europe large enough to repair Germany's giant battleship Tirpitz. If it could be put out of action the chances of the Nazi raider threatening Britain's Atlantic lifeline would be greatly reduced. On 26 March 1942 the destroyer HMS Campbeltown, packed with commandos and explosives set out on a daring mission to achieve this.

The French port of Bordeaux was vital to Hitler's war machine. Through it came many of the vital raw materials from the Far East essential to keep the Nazi armies fighting. But Bordeaux was 90 miles up the heavily-guarded Gironde river and seemingly unassailable. Then Royal Marine Major 'Blondie' Hasler came up with the idea of a sending a special raiding force in canoes.

As Britain faced Nazi Germany alone in July 1940, Winston Churchill's response was to set up the Commandos - an elite fighting force to raid enemy coasts. In December 1941 on his orders a major assault on Vaagso in northern Norway, convinced Hitler that the country was a vital strategic target. Subsequently more than 250,000 Nazi troops were pinned down there uselessly for the rest of the war.