You've seen the vast crowds, you've heard the angry chants. But do you have any idea what Ali Akbar Hashemi Rafsanjani is up to?
Iran's political crisis remains on a knife-edge, a week after a presidential election that plunged the country into its deepest turmoil since the revolution 30 years ago. And a great deal depends on how it all ends.
Which is why I would so dearly like to know what Mr Rafsanjani is up to. (You'd easily recognise him: he's the one major Iranian political leader who doesn't have a beard. And if you've ever looked at the picture at the top of this blog, you'll understand why I notice these things.)
Hashemi Rafsanjani is widely regarded as the second most powerful man in the country, after the Supreme Leader, Ayatollah Ali Khamenei. And to many analysts, the titanic struggle now under way on the streets of Tehran and many other major cities is not so much between supporters of the two rival presidential candidates, but a much more significant battle between Khamenei and Rafsanjani.
Here's what you need to know about him. He was President from 1989 to 1997, ran again in 2005, but was defeated by Mahmoud Ahmadinejad. Ayatollah Khamenei made no secret of his preference for Rafsanjani's rival, so there's what you might call a history between them.
(UPDATE, 1345: According to the , in his Friday prayer sermon, Khamenei "criticized Ahmadinejad for accusing Rafsanjani of corruption, defending him as a pillar of the establishment. But he ultimately took Ahmadinejad's side in an ongoing dispute between the two men, who ran against each other in the 2005 presidential elections.
"Since 2005 there has been a difference of opinion between these two men on foreign affairs, social, cultural and economic issues," he said. "Ahmadinejad's opinions are closer to mine.")
Now, however, Rafsanjani holds two immensely powerful positions at the heart of Iranian politics: he's chairman of the Assembly of Experts, which has the power to appoint and dismiss the Supreme Leader, and he's chairman of the Expediency Council, which arbitrates between the parliament and the Council of Guardians, which approves all political candidates and is meant to ensure that the country's constitution is respected. (He's also very rich, with extensive business interests, which has led many critics to accuse him of corruption.)
He has a reputation as a consummate wheeler-dealer, and was a key influence behind the scenes during the campaign of the reformist presidential candidate Mir Hussein Mousavi. For years, whenever a political crisis has loomed, Iranians have asked: What is Rafsanjani up to now?
Well, whatever he's been up to over the past week, he's been keeping very quiet about it. As far as I know, there hasn't been a single public word from him since the election results were declared.
If the hope of the conservative elite was that the protests would die down after a few days, it looks as if they may have been wrong. I'm told that during yesterday's silent protests, it took the marchers two hours walking 15-abreast to pass by ... one estimate was that there were 750,000 people out on the streets of Tehran alone.
With every passing day, the pro-Mousavi protesters seem to be gaining in confidence. They know from the pictures they pass on to each other on the internet and on their mobile phones that they are far from alone. And they know from the uncertain response from the authorities that the power structure is confused.
Take a look at a map: on one side of Iran is Iraq, and on the other is Afghanistan. In both those countries, as well as in Lebanon, Syria and Israel, and further afield, governments are waiting anxiously to see what happens next in Tehran.
The irony is that the presidential challenger, Mr Mousavi, is no radical - far from it, in fact: he was until very recently a fully paid-up member of the ruling conservative elite. But now he has been cast into the role of opposition leader, a role he seems to have adopted, to the surprise of many, with some alacrity.
Nevertheless, I'm still waiting for the next move by the man they call "the shark", Hashemi Rafsanjani. If he decides openly to challenge Ayatollah Khamenei, then, to use a phrase quite unfitting for a Muslim nation, all bets are off. And many Iranian analysts fear that this crisis could become a lot more serious before it's over.
