‘Good as new – it healed in less than a fortnight. How’s Charlie? Did he get better?’

Ewan felt a surge of boiled anger through his arteries. Whether it was his temper or the approaching fires, he couldn’t tell.

‘Oh,’ said Roth. ‘Still dead then.’

‘You killed him on his birthday.’

‘Who gives a crap?’

‘Me. And I’m amazed you even remember his name.’

‘Well, yeah!’ said Roth with an enthusiastic grin pointed through the glass. ‘I love learning about the people I’ve killed! Beth Foster… Miles Ashford… Tim Carson… the Rileys… and another three, including Charlie. You can poke fun at my broken nose until you burn to death in there, but I’ve caused you more pain than you could ever cause me.’

‘Why not open the door and put that to the test?’

‘Nah, I’m alright thanks.’

Something horrible got into Ewan’s throat and sent him into a coughing fit. He had spent the conversation racking his brain for ideas on how to escape a burning room with a locked entrance, and had come up with nothing. Roth was watching his every move. The heat was increasing, the oxygen running low. And Alex was on his way to the nearest stairwell, clueless about Ewan’s troubles and too far away to rescue him anyway.

‘Looks like you took those incendiary grenades from the biorifle soldiers,’ Roth laughed. ‘Aren’t you happy I left them for you? I figured you’d use them to set up your own death trap.’

‘You wanted me to kill a biorifle platoon, just so I could take their weapons?’

‘Unless they killed you first. Either way I’d have been happy. Besides, they’re just clones.’

Ewan’s eyes, watery from the advancing smoke, gazed at the burning floor at the stone pillars. The powdered remains of clone blood between them, long burned away, had proved Grant and Roth’s attitude to their own soldiers.

At that moment, Ewan realised.

That clone was let into the chamber somehow. H e didn’t smash the glass like I did.

There must be a second door somewhere.

‘You alright, Ewan? Not dying on me, are you?’

Ewan didn’t answer. He turned his head, spotted a cupboard with red and white tape, and figured it might have held some emergency equipment. He ran from the entrance, jerked open the cupboard door and found a gas mask. It wouldn’t filter all the smoke, but it was better than nothing. He removed his helmet, rested the mask halfway over his forehead, then returned to the door and pushed the intercom again.

‘I’d love to stay and chat, but I just had my ears talked off by Marshall.’

‘Irritating, isn’t he?’

‘The worst, except for you. Anyway, I’m heading for the other exit – the one inside the chamber. Feel free to chase me.’