Nazanin Zaghari-Ratcliffe is a 43-year-old British-Iranian woman who has been detained in Iran for five years.
The Iranian regime claims that the 42-year-old was working against the state when she was arrested on a visit to the country to see her parents with her daughter in April 2016.
In March, aid worker Mrs Zaghari-Ratcliffe was released from house arrest and had her ankle tag removed after her five-year prison term expired – but she has now been sentenced to another year in jail on charges of "propaganda activities against the regime" in Iran.
How can the Iranians go on holding her?
She should have been on a plane on 8 March when her five-year sentence ended.
Instead, she was hauled back into court to face fresh charges. Now she’s been convicted of "spreading propaganda" after allegedly attending a protest outside the Iranian Embassy in 2008.
So she has to go back to jail?
This is unclear at the moment.
She can appeal, which will take a few weeks. If that fails, her family hope she can be held at her parents’ house under house arrest and avoid prison, where she was subject to torture and psychological abuse.
But on the face of it, it is a year’s sentence followed by a year’s travel ban – meaning she will not see her family for another two years, with no guarantee after that.
Sounds like more trumped up charges. What’s really going on?
The Iranians have not suddenly found damning new evidence against Nazanin. In fact they’ve failed to present any evidence for five years to support the charges against her.
They are holding her for other reasons. In the words of Tom Tugendhat MP, who heads the commons foreign affairs select committee, she is being held as a hostage as leverage.
Leverage for what?
A decades-old debt Britain owes Iran for tanks it paid for in the 1970s – but never received.
What has a mother being held in a jail in Iran got to do with tanks?
Under the Shah of Iran, Iran paid £400m for an order of Chieftain tanks – but once the Iranian revolution installed a regime uncongenial to the UK, the tanks were never delivered.
Was the money returned?
No – but in 2008, an international court of arbitration ruled it should be.
Instead, the UK paid it into a frozen bank account where it has remained ever since, while the two countries wrangle over issues like the interest owed on the money and who it should be paid to.
So what’s the connection with a mother being held against her will in Iran?
The Iranians have made it clear, but never officially, that her fate is linked to the money being repaid.
They say there is no reason the UK does not cough up the cash.
The UK has only recently admitted there is a link.
Do the Iranians have a point? If Britain owes the money, surely it should pay up?
It’s not as simple as that, says the British government. It does not want to reward Iran for taking people prisoner.
And there is the question of who is paid the money. Branches of the Iranian government are regarded as terrorist organisations and it would breach sanction to pay them.
Can we buy that?
Up to a point.
But it is 13 years since a court ordered the money paid and in that time they have failed to find a way to do so.
The debt case was due to return to court this week, but the Iranians asked for it to be adjourned. Nazanin’s hushand Richard Ratcliffe says the Foreign Office should have done more to stop it being postponed yet again.
Can the UK government do anything else to help her?
Yes, say groups like Amnesty International.
They should make the most of the diplomatic protection they gave her back in March 2019.
They should insist on providing Nazanin with consular assistance, as is their right under international law.
And they should work with other countries to stop Iran’s temporary detention of staff.
Are there others like Nazanin suffering the same fate?
Yes, probably around a dozen.
Some have come forward – others have taken Foreign Office advice to keep a low profile. And that’s just the UK.
Iran has taken a number of other nationals and will probably continuing doing so until it is punished for what has been branded "hostage diplomacy" – seizing innocent people to gain an advantage in negotiations with their governments.