My Life As A Traitor, by Zarah Ghahramani with Robert Hillman

Mesmerising memoir of 30 days in the life of a brutalised Iranian teenager

Yet another ghosted prison memoir? Yes, but this one is different. As a first-hand account of an experience evoking both the fictions of Kafka and the factual martyrdom of Lorca – ironically, the teenage Zarah Ghahramani's literary deities – it exerts mesmerising power. But as a chronicle of life in Iran it highlights aspects of this easily demonised country that totally escape the Western media. It comes as a shock to realise that the London Blitz was but a pale prefiguring of the devastation wrought on Iranian society by the eight-year war with Iraq.

Ghahramani's father served the Shah as a senior army officer, but stayed on as a humble shopkeeper after the revolution. He and his wife trained their children to respect tolerance and decency, and to adapt to the mullahs' rules outside their home. While he was a Muslim, she was a Zoroastrian. The author argues the literary superiority of Farsi over Arabic, and stresses her Persianness, "which allows me to embrace the whole of my country's history". Surprisingly late, she also reveals that her family is Kurdish, and therefore as historically attuned to pragmatic accommodations as Jews are in Europe.

Ghahramani plays down her incriminating prominence as a student feminist. But life inexorably radicalised her, most dramatically when her beloved cousin was driven to escape a forced marriage by burning herself alive. Ghahramani's nightmare – 30 days of extreme maltreatment and mortal terror – began when she was scooped off the street and banged up in Evin prison, where "politicals" were hanged after breakfast each day. Her account intersperses poignant flashbacks into childhood with unbearable present reality. The voice telling this story is remarkable in its combination of grace, wit and evocativeness.

Psychologically, it's very acute. Ghahramani gives us the scene – the tiny cell, the blindfolds, the humiliating toilet rituals – and vividly describes the interrogators she can't see. She delineates her quasi-marital whispered relationship with the half-mad surgeon in an adjoining cell. And she shows, step by step, how her self-respect is destroyed, her will broken, by ever-more brutal beatings.

If Hollywood wants a sequel to Ariel Dorfman's Death and the Maiden, here it is. I won't spoil one of the pleasures of this book by revealing its real-life denouement, which comes with the improbable neatness – and cathartic power – of a dream.

Bloomsbury, £12.99. Order for £11.69 (free p&p) on 0870 079 8897