The floor was occupied by a sniper, who lay on his front with both hands wrapped around a rifle that had been fixed in position. When Kate looked at his short mattress, she discovered why Grant could afford to design the rooms so small.

She was looking at half a clone. Its body ended at its waist, with a perfectly formed head, shoulders and arms, and a torso large enough to contain its vital organs. Clearly, Nathaniel Pearce had decided not to waste resources on legs they would never use. The clone model was built for the specific purpose of sniper duty, and the design of their bodies – like the absence of vocal cords – must have made them easier for Grant and Pearce to control.

Kate used her childhood gymnastics experience to walk lightly on her toes, ensuring her approach was silent.

She almost felt sorry for the half-clone; she could only imagine how long the sniper had laid there, or how his attention span had coped with continuous, unrelenting sniper duty. But nonetheless, this clone would be as determined to kill her as any other. Kate slid her knife from its sheath, held her breath and bent over the clone on the mattress like a sinister tooth fairy.

‘Guys!’ Ewan’s voice yelled from her radio. ‘Good news!’

Kate leapt in horror. The clone on his mattress rolled over with panic across his face. He fumbled for the handgun on the belt around his stumped abdomen, but his vision was obscured after hours of having one eye closed and the other through a telescope. Kate fell to the mattress knife first, and stabbed it into the front of her victim’s neck.

‘Is this important?’ she whispered. ‘I’m… busy.’

The clone’s eyes rolled up towards his brain, and Kate watched his face for fading signs of life. She noticed how little she regretted her actions, or even felt anxious about killing a clone from inches away, given the urgency of the night’s mission. She was proud and alarmed in equal measure.

‘Two targets down, three to go!’ Ewan screamed, thankfully after Kate had turned the volume low. ‘I just destroyed the Experiment Chamber!’

‘Make that three targets down,’ answered McCormick’s voice. ‘The archive was closer than I thought.’

‘It’s gone already?’

‘Paper burns very quickly. There are no more written records of AME left in existence. Just the backup server to go now, then we can storm Marshall’s office and put an end to AME forever.’

‘Oh,’ said Ewan, ‘and just while we’re talking… I killed Oliver Roth.’

Kate froze in disbelief.

‘Oliver Roth?’ said Alex. ‘You’ve got to be kidding.’

‘Four bullets in the torso, then I locked him in a burning room. I’m pretty sure we can go home tonight and declare once and for all that he’s dead!’