When one of the world's most promising chess players, 25-year-old Sara Khadem, decided to play at an international tournament without her headscarf, in solidarity with the protest movement in Iran, she thought a warning would be the worst that would happen to her.

Instead, she can't return to Iran - there are arrest papers waiting for her, and she now lives in exile in southern Spain, with her husband and one-year-old son.

She and her family asked the BBC not to reveal her precise location; their worry is that there may be repercussions even thousands of miles away from Iran.

Women in Iran are required to wear headscarves in public, even when abroad. But a few are choosing not to, in support of the women and girls spearheading the protests inside the country, following the death in custody of 22-year-old Mahsa Amini in September. One of them, the climber Elnaz Rekabi, was forced to recant and it is unclear what her situation is, now that she is back in Iran.

Sara Khadem said there was a slow evolution of her decision to play in the tournament in Kazakhstan in December last year without her headscarf. The contestants only wore them in front of the cameras, and she felt that was hypocritical. Given the sacrifices being made by the women and girls on the streets of Iran, some of them risking their lives, it was the least she could do, she said.

Had she considered joining the demonstrators herself? "Yes of course," she replied. But her young son, Sam, held her back. She said: "I have responsibilities to him, and I thought perhaps I could use my influence in other ways."

Sara Khadem has been playing chess competitively since she was about eight years old. This is not the first time she has fallen foul of the Islamic Republic's strict codes of behaviour.

In 2020, a Ukrainian plane which took off from Tehran airport was shot down by, as it turned out, the Iranian Revolutionary Guard Corps, killing 176 people. It was three days before the authorities admitted their error. Ms Khadem said on social media she was planning to leave the national team. She did not mention the flight - nevertheless, she was forced to sign a confession saying she did not mean anything political by her post.

The next time she went to the airport, her passport was confiscated. She thought her career was over.

Now that her life has changed utterly, does she have any regrets? Without hesitation she said no. "I miss my family, but I would not say I regret the decision. I still represent Iran, and I am Iranian, and the people of Iran still see me as Iranian."

It struck me that she does not regard herself as political, though she acknowledges that so much in Iran is political. She said, "I'm not an activist, and I don't have any messages for people risking so much. The people who are protesting in the streets are inspiring to me and so many others."

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Her husband, Ardeshir Ahmadi, is a film director and internet show presenter, who has also had direct experience of being on the wrong side of the Islamic Republic. A documentary film about hip hop resulted in him being beaten and imprisoned for three months. The decision which led to their exile was a joint one.

She has been able to stay in Spain because of the golden visa rule, which allows anyone who buys a property valued at half a million euros (£442,000; $536,000) to gain residency.

Prime Minister Pedro Sánchez invited Sara Khadem to meet him. The day turned out to be bittersweet.

"It was on that day that I was issued with arrest orders at home. So I had mixed feelings: I was appreciated in this country - and in my own country, where you have achieved lots of success, you get arrest papers."