I got down one flight of stairs without seeing anyone; on the second there were two girls who looked not long out of school, on the landing whispering to each other and giggling. Interns catching up on last night’s gossip. They went quiet as I came past, giving them a nod. I kept going. One more flight of stairs to the vaults. I came out the door and into a narrow corridor. The right led to the vaults, the left to the Ryder Street delivery door.

To my right was empty.

To my left there was a broad back in a pinstripe suit walking towards the exit.

‘Eyes on Frederick,’ I spoke softly.

‘Take him alive, Lex.’ Hattie’s voice came in through my earpiece. ‘You can’t risk firing. If there’s a bomb he could be wearing a trigger vest.’

I took a deep breath and walked towards him.

He stopped. And turned around slowly.

‘Hello, Lex.’

‘Frederick.’

‘Now, let’s not make a scene. Lots of innocent people around here. And let’s face it, I could crush you without even really trying. Although I don’t usually hit women. It’s just not—’

I punched him in the face before he could finish.

He may have been bigger than me. He may have even been stronger. But he didn’t have the training. He hadn’t spent a year at the Farm. Learning how to fight. Learning how to kill. He thought he could beat me. The trained Rat. Because he was a boy. And I was a girl.

Before he had time to recover from the blow to the face I struck again with three sharp jabs to his lower torso. He bent over and dropped to the floor, winded.

Laughter and voices were coming up the corridor from the Ryder Street entrance.

I roughly pulled Frederick off the ground and propped him up against the wall. He clutched his stomach.

A couple of porters entered the corridor, pushing a trolley with several boxes on. One was regaling the other with his antics from the night before.

‘Why, Frederick? All this just to get rich?’ I spoke quietly. We needed to talk. We needed to be written off as two suited colleagues having a conversation.

Frederick shrugged. ‘I was bored of my life. I wanted a better one. With nicer things.’

‘Thatcher knew you were the Snake, didn’t he?’

The porters passed right by us; they didn’t even look at us as they continued their conversation about a girl with a frightening amount of facial hair.

‘It was my fault. I got lazy. Letting four missions from the same department tank was too much. It was always going to draw attention. Our business model was always for Tenebris to be a high-income earner for a year and then disappear. And now we get to go out with a bang.’

The porters kept going down the corridor with the trolley towards the vaults.