There was a sound of splintering wood. ‘Keleedha!’ someone shouted excitedly; Martin didn’t need that translated for him. People started passing jangling bunches of keys back through the crowd. A man in front of Martin offered him a bunch; Martin shook his head apologetically. ‘Ruznaame negaaram. Momken nist.’

Behrouz held out his hand and took them.

The protesters spread out, looking for the cells their keys would open. As Martin followed Behrouz to the crowded stairwell, he saw a woman ahead of them turn at the landing and he glimpsed Mahnoosh’s face in profile. He felt a sudden ache of panic in his chest; he wanted to call out to her, to plead with her to be careful, but he was afraid that might sound presumptuous.

On the third floor there were two more metal gates that needed power-tools to break through; it was another twenty minutes before they were standing before the cells themselves. Martin raised his phone and snapped the scene: a row of identical doors stretching away down the corridor ahead of them, with no windows, just thin slits that appeared to be bolted shut. The place was shabbily clean, with a strong smell of disinfectant not quite masking an undercurrent of excrement. Even now, Martin could hear only faint, muffled shouting from a few inmates; the cells were almost soundproof.

The first key was matched, the first door swung open. A middle-aged man limped out into the corridor; he seemed dazed, unsure of what was happening. He was dressed in loose white clothes, bare-foot; above his thick beard his face was covered in welts and bruises. He spoke with his liberators in a soft voice, with an air of puzzlement. Maybe he’d heard nothing of Jabari, of the strikes and marches. Perhaps he’d spoken to no one but his captors for years.

Martin held up his phone and started filming.

Behrouz said, ‘I’m going this way.’ He shook his keys and gestured at a second line of cells that started further to their right.

‘Okay.’ Martin didn’t follow him; he wanted to record what was happening, but he didn’t want to thrust his camera into the faces of these fragile people. Another door opened in the corridor ahead of him; a tall, skinny youth, shirtless, with long red weals on his back, stepped forward nervously. As he talked with the protesters he was as quiet as the first man, but much more anxious, blinking and flinching away from anyone who came too close. Then he sat down on the floor outside the cell and cradled his head in his arms.

When the third cell opened there were shouts of jubilation; Mahnoosh was among the liberators here, cheering the loudest. After a moment Martin recognised the freed prisoner as a young man who’d been arrested on the first day of the siege; his face was bruised and one eye was swollen shut, but he was still wearing torn street clothes rather than prison garb. Some of his friends lifted him up on their shoulders and carried him towards the stairs.

As Martin turned to keep them in view, he heard a gunshot, very close. One of the protesters staggered, bleeding from the shoulder. Martin swung around, his ears ringing in the silence. A man with a neatly trimmed beard, wearing a pale green shirt decorated with the prison authority insignia, was standing a few metres away, in front of an open utilities closet.

The guard turned to Martin, shouting angrily, gesturing with his pistol. Martin raised his hands in surrender, but the guard kept screaming insults or instructions. Martin had no idea what he was saying, and the only response he could string together was an apology for his incomprehension: ‘Ma’zerat mikham, agha. Farsi balad nistam.’

The guard aimed his gun directly at Martin’s head.

Mahnoosh called out urgently, ‘Put down the phone! He wants you to put down the phone!’

Martin tried to drop it, but his fingers wouldn’t unclench. He wished he’d taken the keys when he’d been offered them.

The guard grunted and sagged to the ground. Someone had hurled a fire-extinguisher and hit him in the back. People piled on top of him, grabbing the gun and restraining him. Martin felt lightheaded; he sat on the floor and watched, detached from everything. The guard was taken to a newly vacated cell; the wounded protester was given a makeshift bandage and helped to the stairs. There was a hospital in the prison complex, Martin recalled. He wondered if they’d be willing to treat the man.

‘Hey! Martin jan!’

Martin looked up to see Omar approaching, with Behrouz following behind him. His face was gaunt and he was walking with a limp, but he was beaming. Martin rose to his feet and stepped forward to embrace him, fighting back tears of relief.

‘What happened? It looks like you lost twenty kilos.’

‘I did a hunger strike,’ Omar replied. ‘Looks like it worked. Twenty kilos and the walls come down; ten more and they would have made me President.’

Omar wanted to phone Rana. The protesters had managed to force open two offices with working landlines, but there were already long queues for those, so they decided to try the floor below. As the three of them were walking down the stairs, Martin’s phone emitted a chime he’d never heard before. He checked the display, and after a moment he realised that it was now showing an icon for the radio mesh network that he’d seen used at the Majlis protest. Someone must have found the local jammer and disabled it.

He showed Omar, who tried a few numbers, but the network was still jammed across most of the city. On the second floor one of the landlines was free; while Omar was making his call, Martin’s phone managed another novel sound. Someone on the network was offering a streaming video feed.

He tapped the icon, and it expanded into a shaky camera shot of a TV screen tuned to an IRIB news broadcast. Martin gave the phone to Behrouz.

Other people around them were already cheering ecstatically. Behrouz scowled, struggling to hear more. Martin waited patiently; there was a loop of text running at the bottom of the screen, it would all be spelled out eventually.

Behrouz said, ‘The moderate clerics have won some kind of deal. There’s going to be a referendum on the Guardian Council veto powers within three months, followed by new elections for the President and the Majlis before the end of the year.’

That was it, that was the saving move. If the deal held, there would be no civil war, but no turning back to the status quo either.

Omar was sitting on the floor, the office phone in his hand, weeping with joy. Behind him was a huge grey filing cabinet that someone had tipped on its side, spilling VEVAK’s meticulous accounts of their interrogations all over the floor. Maybe there hadn’t been enough time to put everything through the shredders. Or maybe the fuckers had thought they’d be coming back.

Martin turned to Behrouz and held out his hand. ‘Mubaarak.’ Behrouz shook it, but even as his expression of disbelief slowly melted into a kind of stunned acceptance, he wasn’t ready to claim victory.

‘Nothing’s certain yet,’ he insisted.

‘No,’ Martin conceded.

Behrouz smiled. ‘But it starts today. It might take us another ten years to be free – but it starts today.’