Welcome to the documentary from the BBC World Service.

This is the fifth floor.

The fifth floor, you knowssonous.

This is the fifth floor at Farnak Amidi Sobeth. This is the fifth floor at the heart of global storytelling with BBC journalists from all around the world.

I'm your host, Farak Amidi.

Evin Prison in the north of Tehran is a well-known, somewhat notorious place in Iran.

Everyone has an image of Evian prison in their heads,

but not many people know what goes on in there and how life actually is for the prisoners.

It's certainly not a place where you would expect much singing.

That is the sound of female prisoners in the women's ward of Edin.

They are singing a protest song, calling for freedom

and an end to the death penalty. Thousands of women in Iran have been arrested since the

Women Life Freedom protests in 2022, and a large proportion of them are held in Avine. Through multiple reliable sources,

BBC Persian have been piecing together an idea of what life is like in the prison and made

an animated film called Songs from Inside. Golnush Golshani worked on the film. She's from Iran herself, so I spoke to her

about what it was like, finding out about these women and telling their stories. So tell me about

this particular prison, Avin. I mean, we hear the name all the time, but what is it known for?

You're right. It's one of the best known prisons in Iran. It's got a reputation as being a notorious prison and the reason

behind it is both before the revolution of 1979 and mainly after that, it's been the prison where most of the so-called political prisoners have been kept in.

The numbers have grown during different periods, especially after the Iranian Revolution.

In different periods, large number of executions of such political prisoners have taken place in the prison.

It's located north of the capital, Tehran.

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