After the assault on the stock exchange of Saeed and Nadia’s city, it seemed the militants had changed strategy, and grown in confidence, and instead of merely detonating a bomb here or orchestrating a shooting there, they began taking over and holding territory throughout the city, sometimes a building, sometimes an entire neighbourhood, for hours usually, but on occasion for days. How so many of them were arriving so quickly from their bastions in the hills remained a mystery, but the city was vast and sprawling and impossible to disconnect from the surrounding countryside. Besides, the militants were well known to have sympathisers within.

The curfew Saeed’s parents had been waiting for was duly imposed, and enforced with hair-trigger zeal, not just sandbagged checkpoints and razor wire proliferating but also howitzers and infantry fighting vehicles and tanks with their turrets clad in the rectangular barnacles of explosive reactive armour. Saeed went with his father to pray on the first Friday after the curfew’s commencement, and Saeed prayed for peace and Saeed’s father prayed for Saeed and the preacher in his sermon urged all the congregants to pray for the righteous to emerge victorious in the war but carefully refrained from specifying on which side of the conflict he thought the righteous to be.

Saeed’s father felt as he walked back to campus and his son drove back to work that he had made a mistake with his career, that he should have done something else with his life, because then he might have had the money to send Saeed abroad. Perhaps he had been selfish, his notion of helping the youth and the country through teaching and research merely an expression of vanity, and the far more decent path would have been to pursue wealth at all costs.

Saeed’s mother prayed at home, newly particular about not missing a single one of her devotions, but she insisted on claiming that nothing had changed, that the city had seen similar crises before, though she could not say when, and that the local press and foreign media were exaggerating the danger. She did, however, develop difficulties sleeping, and obtained from her pharmacist, a woman she trusted not to gossip, a sedative to take secretly before bed.

At Saeed’s office work was slow even though three of his fellow employees had stopped showing up and there ought to have been more to do for those who were still present.

Conversations focused mainly on conspiracy theories, the status of the fighting, and how to get out of the country – and since visas, which had long been near-impossible, were now truly impossible for non-wealthy people to secure, and journeys on passenger planes and ships were therefore out of the question, the relative merits, or rather risks, of the various overland routes were guessed at, and picked apart, again and again.

At Nadia’s workplace it was much the same, with the added intrigue that came from her boss and her boss’s boss being among those rumoured to have fled abroad, since neither had returned as scheduled from their holidays. Their offices sat empty behind glass partitions at the prow and stern of the oblong floor – an abandoned suit hanging in its dust cover on a hat rack in one - while the rows of open-plan desks between them remained largely occupied, including Nadia’s, at which she was often to be seen on her phone.

Nadia and Saeed began to meet during the day, typically for lunch at a cheap burger joint equidistant from their workplaces, with deep booths at the back that were somewhat private, and there they held hands beneath the table, and sometimes he stroked the inside of her thigh and she placed her palm on the zip of his trousers, but only briefly, and rarely, in the gaps when it appeared waiters and fellow diners were not looking, and they tormented each other in this way, since travel between dusk and dawn was forbidden, and so they could not be alone without Saeed spending the entire night, which seemed to her a step well worth taking, but to him something they should delay, in part, he said, because he did not know what to tell his parents, and in part because he feared leaving them alone.

Mostly they communicated by phone, a message here, a link to an article there, a shared image of one or the other of them at work, or at home, before a window as the sun set or a breeze blew or a funny expression came and went.

Saeed was certain he was in love. Nadia was not certain what exactly she was feeling, but she was certain it had force. Dramatic circumstances, such as those in which they and other new lovers in the city now found themselves, have a habit of creating dramatic emotions, and furthermore the curfew served to conjure up an effect similar to that of a long-distance relationship, and long-distance relationships are well known for their potential to heighten passion, at least for a while, just as fasting is well known to heighten one’s appreciation for food.

The first two weekends of the curfew came and went without them meeting, outbursts of fighting making travel first in Saeed’s neighbourhood and then in Nadia’s impossible, and Saeed forwarded to Nadia a popular joke about the militants politely wishing to ensure that the city’s population was well rested on their days off. Air strikes were called in by the army on both occasions, shattering Saeed’s bathroom window while he was in the shower, and shaking like an earthquake Nadia and her lemon tree as she sat on her terrace smoking a joint. Fighter-bombers grated hoarsely through the sky.

But on the third weekend there was a lull and Saeed went to Nadia’s and she met him in a nearby café since it was too risky for her to drop a robe into the street by day, or for him to change outdoors, and so he pulled it on in the café’s bathroom while she paid the bill and then with his head covered and eyes on the ground, followed her into her building, and once upstairs and inside they soon slipped into her bed and were nearly naked together and after much pleasure but also what she considered a bit excessive a delay on his part she asked if he had brought a condom and he held her face in his hands and said, “I don’t think we should have sex until we’re married.”

Later as they lay in bed listening to an old and slightly scratched bossa nova LP, Saeed showed her on his phone images by a French photographer of famous cities at night, lit only by the glow of the stars.

“But how did he get everyone to turn their lights off?” Nadia asked.

“He didn’t,” Saeed said. “He just removed the lighting. By computer, I think.”

“And he left the stars bright.”

“No, above these cities you can barely see the stars. Just like here. He had to go to deserted places. Places with no human lights. For each city’s sky he went to a deserted place that was just as far north, or south, at the same latitude basically, the same place that the city would be in a few hours, with the Earth’s spin, and once he got there he pointed his camera in the same direction.”

“So he got the same sky the city would have had if it was completely dark?”

“The same sky, but at a different time.”

Nadia thought about this. They were achingly beautiful, these ghostly cities – New York, Rio, Shanghai, Paris – under their stains of stars, images as though from an epoch before electricity, but with the buildings of today. Whether they looked like the past, or the present, or the future, she couldn’t decide.

The following week it appeared that the government’s massive show of force was succeeding. There were no major new attacks in the city. There were even rumours that the curfew might be relaxed.

But one day the signal to every mobile phone in the city simply vanished, turned off as if by flipping a switch. An announcement of the government’s decision was made over television and radio, a temporary anti-terrorism measure, it was said, but with no end date given. Internet connectivity was suspended as well.

Nadia did not have a landline at home. Saeed’s landline had not worked in months. Deprived of the portals to each other and to the world provided by their mobile phones, and confined to their apartments by the night-time curfew, Nadia and Saeed, and countless others, felt marooned and alone and much more afraid.

Excerpted with permission from Exit West, Mohsin Hamid, Hamish Hamilton.