The slap across my jaw from behind me made my ears sting red with anger and embarrassment. I was being punished for daring to glance around the room where I was being questioned - accused of being a spy for Britain. A few days earlier I had been brought, blindfolded, to the heart of Evin Prison, to begin what my captors believed would be the simple process of establishing my guilt. I was told to sit down, and keep facing the bare wall in front of me, before my blindfold was removed. On a sheet of official notepaper I was to scribble answers to my interrogator's questions. What had I been doing in the days since the disputed Iranian election? Who were my contacts? Who had I interviewed and what had they told me?
When he stepped outside to talk to intelligence ministry colleagues, I briefly craned my neck to see whether the interrogation suite was equipped with a camera. It was a mistake: quick as a flash the official was back, and I was being punished for my disobedience. My face still smarting, I whirled round to confront him. It was a visceral reaction and the only time in a week of almost daily interrogations that I stared straight into the face of one of my captors. What I saw was not reassuring. A scruffy white-flecked beard, a contemptuous mouth curling to reveal a flash of gold fillings, and eyes fixed at me in white anger. "Didn't I tell you never to turn around?" he snapped. "Now turn away from me."
My first interrogator was like that. Sometimes his carefully cultivated voice oozed false sympathy. Occasionally, his solicitousness appeared downright sarcastic. When I refused to reveal the names of my Iranian contacts, he assured me that they need not fear. "They are fellow Iranian citizens like myself, Mr Iason," he purred. "Why would I ever hurt my own flesh and blood?" At other times he flew into blind rages, prodding me aggressively in the back while making a point - perhaps about the perfidy of supporters of Mir-Hossein Mousavi, the presidential candidate who is still disputing the outcome of the election. "You think you're treated so badly," he snapped at me, "but what is our treatment in London or Heathrow? Every time in that airport it is four or five hours interrogation for us."