Hari Vikram studied the stranger for a moment; the fact that he was the only one not coated in a thick layer of chalky dust wasn’t wasted on him. ‘Wait! You are clean. How did you get in here? Is there another way through?’

The man shook his head. ‘No.’

‘But… you were not with us before the floor collapsed! There must be some way — ’

‘I have only just arrived,’ replied the man, ‘and I must leave soon. We really don’t have much time.’

Sal’s mother stepped towards him. ‘Leave? How? Can you… can you help us?’

‘I can help only one of you.’ His eyes rested on Sal. ‘You… Saleena Vikram.’

Sal felt every pair of eyes in the stairwell settle on her.

‘Take my hand,’ said the man.

‘Who are you?’ asked her father.

‘I’m your daughter’s only way out. If she takes my hand… she lives. If she doesn’t, she will die along with the rest of you.’

One of the young boys began to cry. Sal knew him; she’d babysat the Chaudhry boys. He was nine and terrified, clutching his favourite soft toy — a one-eyed bear — tightly in both hands as if the bear was his ticket out.

Another deep moan from one of the skyscraper’s structural support bars echoed through the small space on the stairwell, like the mournful call of a dying whale, or the stress vibration of a sinking ship. The stale air around them, already hot, was becoming almost too painful to inhale.

‘We have just over two minutes,’ said the man. ‘The heat of the fire is causing the building’s framework to deform. Palace Tower will collapse, directly in on itself at first, then sideways into the mall below. Five thousand people will be dead a hundred and twenty seconds from now. And tomorrow the news will be all about the terrorists who caused this.’

‘Who… who are you?’ asked her father again.

The man — he looked old, perhaps in his fifties or sixties — stepped forward through the crowd, his hand extended towards Saleena. ‘We don’t have time. You have to take my hand,’ he said.