Timewatch - Season 30 / Year 2011

Documentary that reveals the secret story behind one of the greatest intellectual feats of World War II, a feat that gave birth to the digital age. In 1943, a 24-year-old maths student and a GPO engineercombined to hack into Hitler's personal super-code machine - not Enigma but an even tougher system, which he called his 'secrets writer'. Their break turned the Battle of Kursk, powered the D-day landings and orchestrated the end of the conflict in Europe. But it was also to be used during the Cold War - which meant both men's achievements were hushed up and never officially recognised.

James Holland presents an analysis of the legendary 1943 Dam Busters raid, a low-level night mission that took 19 Lancaster bombers deep into the heart of enemy territory to destroy German dams with a brand newweapon - the bouncing bomb.

Following on from his documentary Operation Mincemeat, based on his book of the same name, writer and presenter Ben MacIntyre returns to the small screen to bring to life his other bestselling book - Agent Zigzag.

As part of the Timewatch series, MacIntyre reveals the gripping true story of Britain's most extraordinary wartime double agent, Eddie Chapman. A notorious safe-breaker before the war, Chapman duped the Germans so successfully that he was awarded their highest decoration, the Iron Cross. He remains the only British citizen ever to win one.

Including remarkable and newly discovered footage from an interview Chapman gave three years before his death in 1997, the programme goes on the trail of one of Britain's most unlikely heroes - a story of adventure, love, intrigue and astonishing courage.