As we walk through the heart of Iran's capital we see a large digital clock nestled among several shops.
It's counting down to what it claims, is the time left until the state of Israel is destroyed.
The clock overlooks Palestine Square in Tehran as cars and vendors come and go in a country that is in conflict internationally and at home.
Across the square is a billboard, several stories high, depicting Israeli Prime Minister Benjamin Netanyahu in a straitjacket.
In Hebrew and in Farsi the billboard declares he is "clinically insane".
It's posturing, and propaganda, but this is a country on the brink of war.
Access to Iran is restricted for foreign media. But in June, Iran held a presidential election and ABC's Four Corners was allowed into Tehran for one week.
We were accompanied by a government "minder" and were not free to travel or to see people and places that had not been approved.
One event we were allowed to film was the Supreme Leader of the Islamic Republic of Iran, Ayatollah Ali Khamenei, voting in the election.
We stood among jostling local journalists watching as the 85-year-old shuffled across a large room to place a ballot in a box.
He's not just the most powerful man in Iran, but one of the most influential spiritual and political leaders in the Shia Muslim world.
The snap-election was held after the man Ayatollah Khamenei had wanted to succeed him, president Ebrahim Raisi, was killed in a helicopter crash in May this year.
This is the image the regime wants the world to see.
We didn't have to stray too far from our planned tour to get a sense of its control.
At a rally for the now-President Masoud Pezeshkian, we watched as a gathered crowd were told the reform candidate's rally was cancelled.
Police tried to clear the supporters who had gathered.
One person in the crowd told Four Corners it was an attempt to censor candidates in the closing days of the election.
Soon, uniformed and undercover police surrounded our crew, demanding we turn off our camera.
The police attempted to wrestle the camera from us. We were questioned and ordered to delete the footage.
After half an hour, we were released, footage intact.
The brink of war
The Middle East is teetering on the precipice of a regional war.
In October, Hamas broke through the southern Israel border and killed 1,195 people and took 251 hostages, according to Israeli authorities.
Since then, Israel has been exchanging fire with Iran and its proxies – Hezbollah in Lebanon, the Houthis in Yemen and Shia militias in Syria and Iraq.
Tensions ratcheted up further in the past 48 hours, when Israel bombarded multiple targets in Lebanon and Hezbollah launched hundreds of rockets — the most intense cross-border attacks in months.
[Map]In July, political chief of Hamas Ismail Haniyeh, the group's lead negotiator, was assassinated while in Tehran. Israel has not taken responsibility for the killing but has been accused of orchestrating it.
Netanyahu said afterwards that Israel had dealt Hamas and other Iranian-backed groups "a crushing blow".
Experts say Iran's regime is now feeling the pressure to respond.
But the regime is not just dealing with external pressures.
'An unstable system'
Iran has its own internal unrest. It is a young country ruled by old men.
About 72 per cent of its population was not born at the time of the "Islamic Revolution" of 1979 – when the theocratic authority led by the Ayatollahs seized power after the US-backed regime was forced from power.
Two years ago, young people – women in particular – took to the streets in protest after 22-year-old Mahsa Amini died in custody when she was arrested because her hijab did not sufficiently cover her hair.
The so-called "morality police" detained her.
She later died in custody.
Ali Ansari, professor and founding director of the Institute of Iranian studies at the University of St Andrews in Scotland, said Iran is far from stable.
"It's a volatile system, an unstable system, and one that's vulnerable to all sorts of change," he said.
"I don't think the regime in its current configuration can last. It's simply not sustainable."
This was my third visit to Iran. What struck me most this time was the number of women not wearing hijabs. That likely would not have been tolerated two years ago – as the case of Amini showed.
While some may have felt empowered to remove their hijab, many of the women we spoke to feared the consequences of talking to media about their decision.
Undercover
Knowing how dangerous it can be for Iranians to speak openly, we commissioned an undercover local team to conduct interviews.
The nine people they spoke to, in four different cities, were all born after the 1979 revolution.
"For us, living in Iran is like hell," one man said, "a hell created by a dictatorial regime for its own people".
He said many Iranians opposed "any kind of warmongering" in the region and his government's position on what some call "the big war" which would see Iran deploying Hezbollah, a proxy in Lebanon.
"Hezbollah's hostilities are funded by the money that comes out of Iranians pockets. They buy weapons with our money and kill innocent people. We have no foreign policy at all. Their policies cause war and chaos in the region."
Another man said: "Iran seeks to dominate the entire Middle East, even other countries. Now they're spending the country's wealth on Hamas, the Houthis in Yemen and Palestine, while many Iranians are struggling with hunger and misery."
A young woman said her generation had been "utterly devastated".
"Our youth has been stolen by the revolution," she said.
"After the [Mahsa Amini] protests, many were executed, tortured and imprisoned. There is a real fear of the government."
Mohammad Marandi, an Iranian academic and political analyst, who's close to the regime; paints a different picture.
"I don't think the Israeli regime would want a direct conflict with Iran, because Iran definitely has the upper hand.
"The danger right now is that since Netanyahu has failed in Gaza and … the image of Israel has been demolished across the world … he may feel that his only option for survival is to carry out a major attack."
Ghost town
For the residents of Kiryat Shemona, in Israel's north, survival has meant deserting their home.
It once housed tens of thousands, but now sits mostly abandoned.
Across Israel's north, 60,000 people have been evacuated. On the Lebanese side of the border, 100,000 have been displaced.
Iran's proxy, Hezbollah has launched more than 1,800 cross-border drone, rocket, and artillery strikes on Israeli territories. Israel has struck over 7,000 targets inside Lebanon according to data from the Armed Conflict Location & Event Data Project.
Israel estimates Hezbollah have an arsenal of more than 120,000 missiles.
Sarit Zehavi, a former army intelligence officer, who lives near Israel's northern border, said it's much more.
"Double it … double [the] amount. 240,000."
She said her life is at risk every day.
"When I look at the options, I'm very worried because one option is a full-scale war. We are not at a full-scale war. It's a kind of a war of attrition now.
"It's a terrorist army, working for Iran and it is over here. And we don't have a solution that will prevent all these casualties."
In Tel Aviv, Zohar Palti, a former head of the intelligence directorate of the country's foreign intelligence agency, Mossad, said war has already begun.
"We take it personally when a state is coming, a great state like Iran, and saying that they want to eliminate the State of Israel. And it's coming from the Supreme Leader," Palti said.
In a 2020 speech Ayatollah Khamenei said the "the Zionist regime is a deadly, cancerous growth" that would be "uprooted and destroyed", but has said this "doesn't mean eliminating Jews. We aren't against Jews".
While we are in Israel there's an attack from one of Iran's proxies, the Houthis, who are based in Yemen.
At 3am, an Iranian-made Houthi drone hit the centre of Tel Aviv.
One person was killed – one block from the US consulate and 500 metres from where we were staying.
Former senior Israeli military official Amos Gilad said Iran has positioned itself as Israel's worst enemy.
"Iran used to be our best friend and ally until the Islamic Revolution," he said.
"Iran as a member of the United Nations keeps preaching to destroy Israel, to exterminate Israel."
As both sides tussle for dominance, Jasmine El-Gamal, a former Middle East adviser to the Pentagon during the Obama administration, said any war between Israel and Iran or Israel and Hezbollah would be disastrous.
Her role saw her briefing the chairman of the joint chiefs of the US military.
If she were in that role today and the question of war between Israel and Iran was asked, her answer would be grim.
"I would say 'Sir, I hope we never have to find out'."
And if the chairman insisted on an answer?
"I would say that Iran has the ability through its proxies to light the entire region on fire.
"Regardless of who is left standing on the battlefield, that is a loss for everyone, including Iran and including Israel.
"Israel cannot exist in a region that is completely aflame."
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Credits:
Story by and Jonathan Miller
Photography and video: Ron Foley
Research:
Editing and digital production: and
