In the Democratic Republic of East Germany there had always been rumours that there was a secret police force watching and listening in on people's every move, a hidden entity cataloguing and manipulating people's lives for the benefit of the repressive Communist regime. But it wasn't until 28 years ago when the Berlin Wall came down that the shocking truth was exposed… East Germany had spied on its citizens on a scale never before seen in history.Jamie Theakston looks behind the hidden remnants of this notorious symbol of division to tell the story of East Germany's State Security Service, better known as, the Stasi.