Long after the interrogations at Iran's notorious Evin prison had ceased for the day, Homa Hoodfar's work would begin.
While her cellmates slept, the 65-year-old would lie on the floor, and – using the end of her toothbrush as a makeshift pen – slowly scratch her observations on to the stone walls.
Some days she wrote down her thoughts on the dozens of brutal interrogations she had been subjected to. Other days she scrawled snippets from conversations with other prisoners.
The Canadian-Iranian professor of social anthropology was arrested in June after nearly three months of interrogations by the Iranian intelligence service. After 112 days in prison, she arrived in Montreal last week – freed on what Iran called "humanitarian grounds" – after Canada enlisted the help of Oman.
Nicknamed Evin University, the Tehran prison where Hoodfar was held has housed intellectuals, activists and journalists. But Hoodfar – well known for her work on culture and gender in the Middle East – saw a way to take back some of the freedom that had been seized from her. "I decided, I'm an anthropologist and I'm here, so I can use this as a method of doing anthropological fieldwork," she told the Guardian. "It wasn't fieldwork that I had chosen, it was not a project I wanted to write, but there I was."
The research recast the 30 interrogations she was put through while imprisoned. As she sat facing a wall or a one-way mirror while her interrogators screamed and yelled at her, Hoodfar analysed their choice of words. When they hurled threats at her – "They were telling me, 'You'll get 15 years here and we'll send your dead body back to Canada'" – she contemplated the power dynamics at play.
Interrogators intensified their efforts. A particularly tough moment came after they found a video of her husband's 2014 funeral on her iPad. "They actually played the music that was played at the funeral of my husband." It was a sign of the lengths they were willing to go in order to break her spirit, she said.
Hoodfar's ordeal had begun months earlier, in March, when half a dozen or so members of Iran's powerful Revolutionary Guards raided the Tehran apartment where she was staying. She had been packing her suitcase to return to Canadawhen they confiscated her passports, computer and bags full of books and summoned her to a court date and what would be the first of many interrogations.
She was charged, a state prosecutor later told media in Iran, with "dabbling in feminism and security matters". Released on bail, she was interrogated 12 times. In June, her bail increased fivefold. With little hope of making bail, she was sent to Evin prison.
Hoodfar believes she was targeted as part of the power struggle at play between Iran's elected government, led by Hassan Rouhani, and conservative factions in the country who retain control of the Revolutionary Guards, as well as police and the judiciary in the country. "There's almost two different states functioning at the same time," said Hoodfar. "I was in many ways a pawn in this struggle."
The conservatives were determined to show that Hoodfar had travelled to the country to meddle in the recently held election, pointing to a book she had co-authored on women in parliaments around the world. "They kept asking me if I was a feminist. And I asked them to define what is a feminist – we spent quite a lot of time discussing feminism and the history of feminism in Iran."
She was brought to a tiny cell, some 2 metres by 1.75 metres, but soon moved to a larger cell with Nazanin Zaghari-Ratcliffe, a 37-year-old British-Iranian woman who was arrested in April as she and her daughter were preparing to board a flight to the UK. The two were placed together around the birthday of Zaghari-Ratcliffe's young daughter, said Hoodfar. "She was crying because she was obviously missing her daughter and was worried about her."
The next morning, Hoodfar was moved again. Much of her time in prison was spent in the same bare cell, stripped of natural light. Artificial lights were left on day and night, said Hoodfar. Sleep came rarely. "Sometimes I would go for days without sleeping."
After she was hospitalised for a lung infection, prison staff showed some hints of humanity. At times they sent her fruit juice or brought her food. Eventually she was allowed access to a few books.
One night following two days of gruelling interrogations, she was ordered to be ready at 8am the next day. Six guards escorted her to the apartment where she had been staying to collect her things and insisted she visit a salon to get her greying roots dyed before outfitting her in bright colours. "They wanted me to look good," said Hoodfar.
It was then that she began to suspect that she was about to be released. After a 19-hour flight from Oman spent jotting down the notes she had memorised after painstakingly scratching them on to her cell walls, Hoodfar landed at Montreal's airport last week.
She left behind several dual nationals from the US, UK, Canada and Britain who continue to face questioning or languish behind bars. On Friday, the UN repeated its call on Iran to free Zaghari-Ratcliffe as well as two elderly dual nationals held at Evin who are in need of urgent medical attention.
Their best hope for release, said Hoodfar, lies in the global campaigns and state-to-state relationships to pressure Iran.
Her first days back in Canada were spent rejoicing in the mundane tasks of everyday life, from making a cup of tea in the morning to watering her plants. While much of the reality of her ordeal has yet to sink in, the experience has left her grappling with her identity as an Iranian-Canadian. "I'm heartbroken. I know I'm a Canadian as well and I lived most of my time outside, but I was born there and brought up there and I never felt I was an outsider," she said. "But they treated me like an enemy and that hurt more than the fact that I was in jail."