We now know far more than ever before about the secret world of British intelligence thanks to the Hutton inquiry. Last week at the High Court we heard the evidence of Richard Dearlove the head of SIS, known to most of us as MI6.
Even though his face wasn't shown, this was a remarkable change, once his identity would have been shrouded in secrecy, he'd have been simply called 'C'.
A fascinating history of the world of espionage is opening to the public tomorrow at the National Archives in Kew at a special open day. Dame Stella Rimington, the former head of MI5, will be there to give a talk about the history of the organisation as revealed in the Archives.
Stella Rimington joins Martha to discuss the relationship between the intelligence community, government and the public.